Somali calendar

The Somali calendar () is based on both the solar and lunar calendar systems. The calendar was used by farmers and herders to determine the weather and seasons, it helped them in their needs. The Somali solar calendar is known as Amin-tiris or Shin-tiris while the lunar calendar was known as Dayax-tiriska.
Somali solar year.
The Somali solar year, which is a tropical year in fact, corresponds to the cycle of the seasons. It is based on the weekly cycle and upon the sun, and it is organized into four seasons, twelve months, and 52 weeks plus one day or 365 days. The New Year, which is characterized by a festival called Dabshid falls on or around July 20, in the Gregorian calendar. Other periodic cycles are derived from the weekly cycle in order to create a calendar year and to extend the timekeeping system beyond. As a result, various time units are established. This extended system is based on the number of seven.
Linguistics.
If calendar is defined as grouping of days for conveniently keeping track of prioritized human activities, the proto Eastern Cushitcs had apparently practiced that idea according to the linguistic accounts. The Cushitic terms ‘Tiro’ (count, reckon, number) and ‘Ammin’ (hour, period), which make up the Somali term for ‘calendar’, are themselves several millennia-old for they came from proto Eastern Cushitic language. Tiro is a cognate word from the modern Eastern Cushitics notably the Macro-Somali, Afar, Oromo, Konso, Gawada, and Gobeze. Similarly, the word ‘ammin’ or ‘Amman’ is shared by Macro-Somali, Oromo, Konso and Hadiya. The fact that the common ancestors of the Eastern Cushitics, who lived about six thousand years ago, used these terms indicates that they had to have a way to keep track of the time and a kind of calendar.
As another sign for this early, developed reckoning system, the Proto Cushitic had generally shared most of the numerals including the higher ones such as ‘Kun’ (a thousand) and ‘Shii’ (a thousand or ten thousand ). For instance, ‘tamin’ (ten) of Beja in north eastern Sudan, ‘shii’ of Agaw in north central Ethiopia, and Kuma of Iraqwa in north central Tanzania, are the toman, shii and kun in the Somali. As these four groups represent the Northern, Central, Southern, and Eastern Cushitic respectively, the Somalis are the most easterly group of all Cushitics, who had begun to split 7,000 years ago. This interpretation is supported by a commonality between ancient Somalis and Egyptians. The Somali solar year consists of 365 days, which is similar to the ancient Egyptian calendar. Historians have observed a great deal of cultural and commercial links between the ancient Somalis and their Egyptian counterparts. These ancient peoples are even believed to be descended from common ancestry, at least partially. 11 As a result, cognates appear in astronomical terms as unequivocally shown by the key words in the following table.
Somali-Egyptian astronomical cognates.
In addition to few other terms, such as month and year, these words were the core of calendar language of ancient societies around the world. On the bases of this shared background, it is highly probable that a common heritage had involved the foundations of the two calendar systems, the Somali and the Egyptian. Even with this possibility of common heritage, the Somali calendar appears to have developed indigenously.
Archaeology.
The antiquity and the originality of the Somali calendar is further supported by the belief that the ancient Eastern Cushitics, to which the Somalis belong, developed a sophisticated calendar based on detailed astronomical knowledge by the first millennium BCE (Before Common Era). Researchers have studied the archeo-astronomical nature of two megalithic sites on the southwest part of Lake Turkana, northwest of present Kenya.
The two megalithic sites are locally known as Namoratunga, meaning stone people. Researchers have observed that one of the sites has an alignment of 19 basalt pillars seven of which are non-randomly oriented toward certain stars and constellations that are used by modern Eastern Cushitics ‘to calculate an accurate calendar’.
In addition to this field research, modern archeo-astronomical measures have been used in the study. It has found that the pre-historic Cushitics had been using an accurate, complex calendar system based on astronomical calculation at least twenty-three centuries ago. Namoratunga is located on the southern fringe of a region that was the ancestral home of pre-historic Somalis. The Macro-Somali groups of Rendille, Elmolo, Daasanac (Galab) and Arbore who have been in the area approximately three thousand years are still located very near to these archaeological sites. About four centuries ago when the Turkana and Samburu peoples expanded to the southern part of the lake, they came into contact with these Macro Somali groups, while more Somalis were due east of them. More importantly, the ancient Somalis are known to be ‘demolithic’ (people of stone), who have been associated with tireless building of megaliths. This is shown by the tens of thousands of pre-Islamic-built cairns scattered throughout the Somali inhabited territories. The Cairns are known to the Somalis as Taallo Tiirriyaat (Monuments of Tiirri), or Arro-Weelo graves in some localities. Arro-weelo, literally meaning ruler of the entire land, refers to a legendary queen in the Tiirri Era. Tirri was a powerful, ancient Somali tribe occupying the half of the country including Harar uplands. The term tiir itself means pillar", so tirri means pillar people".
During this same time, another major Somali tribe, Madalle, was creating elaborate stone monuments in the far South (Jubba-Galana region: the vast land southeast of Lake Turkana to the Kismayo-Malindi coast). In addition to other complex earth works, such as flat dams, limestone built wells and ruined towns on the coast, the building of the Taallos is attributed to the Madalle-led ancient Somali communities in the region. Madalle literally means people of congregation, which also refers to power and hard work. Observations of bodies in cairns indicate similar burial practices indicating that they were built by same people.17 However, as they were basically intended to be funeral, they are not related to astronomical phenomena as far as can be discerned.
The evidence suggests that one of the two calendars, Somali and Namoratunga, was the forerunner of the other because of a number of aspects: the Macro Somali groups had been the inhabitants of the region, during what linguistic historians now refer to as the ‘Omo-Tana’ era of Macro-Somali; the Somalis have the most detailed calendar among the Eastern Cushitics; they are builders of megalithic monuments or cairns; the timekeeping system based on ‘seven’ in the Somali culture is also found in Namoratunga, indicating Namoratunga’s connection to the seven-based calendar system that produced the Somali calendar. The two systems, therefore, must be originated from a common cultural aspect or one of them must be derived from the other.
Traditions.
A timekeeping unit based on a week also indicates the antiquity of the calendar. The idea was introduced to different cultures in the world at different times. However, this concept was not common among the ancient or even Pre-European-colonies of the world. The focus of the calendar of many of them was the lunar month, not the week. That was not the case for ancient Somalis. Ancient Somalis gave special importance to the usage of the week in daily life. The present names of the week days in the Somali are Arabic. Besides these week-day names, other seven names were assigned to the timing of days in the week such as Manta (today), Berri (tomorrow), Saadambe (after-tomorrow), Saakuun (after after-tomorrow), Shaley (yesterday), Darraad (before-yesterday) . 
This indigenous week represents the pastoralist version that can be expected from ancient Somalis, and it is further evidence for the existence of pre-Islamic calendar. The seven-day week owes its origin to a reverence for the number seven in the religion of the prophets, the monotheistic messengers such as Noah and Abraham. For instance, seven days, seven heavens and seven earths, are found in the divine religions. In fact, as far as we know, the Israelites were the only people who were using a seven-day week prior to Christianity. All traditional societies, be they African, Asian, Middle Eastern or European, including Greeks and Romans, were using other intervals, that is from 4 to 10 days, or were counting months rather than days.
The Babylonians attached significance to the number seven, and as a result, to the days of lunation that are multiplies of seven. The reason for this honor is unknown; however, it could have originated from previous divine beliefs, namely from the Prophet Noah's religious heritage.
The pre-Islamic Somalis,Oromos, and Rendille believed in a God named ‘Waaq’ or ‘Eebe’, who is the same as Allah or God in Islam and in the other monotheistic beliefs. It is clear that this heritage had come to the ancient Somalis in pre-historic times. Their calendar was, however, constructed for economical purposes rather than ideological concerns, another sign of its pre-Islamic characteristics. Despite the Babylonian beliefs in the sacredness of the number seven, and Egyptian and later Persian calendars based on 12 months of 30 days plus five days, no calendar in the world has been organized like the Somali solar calendar. This idea could have come from the Egyptians, Babylonians or even Persians; however, there is no evidence for this observation. It remains very clear that the Somali's unique organization and method of calculation was undoubtedly developed in Somalia.
The nature of Dabshid celebration also supports the calendar’s existence in prehistoric times. The festival activities, that take one to three days depending on the local customs, contain both Islamic and Non-Islamic aspects. The activities include: building a huge fire; slaughtering animals, mostly goats; playing various games; singing obsolescent songs; and reciting Islamic prayers. The inclusion of non-Islamic customs in the present-day festivities suggests an attempt to preserve some of its pre-Islamic characteristics.
Heavenly-related customs also shed more light on this issue. In this regard, Dirir, Ayaan and Xiddig, have become strong icons in the general culture. Some economic or life events, such as one’s fortune or birth, are marked by the movement of certain stars. The extended, common personal and place names by these terms across the nation reflect the deep rooted-ness of these customs. Although some of these customs are not permitted in the Islamic faith, their persistence within the Islamic culture shows their importance in the daily life of pre-Islamic society, which in turn indicates the age of the calendar.
In Records.
Finally, evidence in the Islamic era appears to show how old calendar foundations have been transformed into the present, remarkably functioning Somali calendar. In his study in 1340's about the history of Awdal, the medieval state in western and northern parts of historical Somalia and some related areas, Al-Umari of Cairo states that in the land of Zayla’ (Awdal) “they cultivate two times annually by seasonal rains … The rainfall for the winter is called ‘Bil’ and rainfall for the ‘summer’ is called ‘Karam’ in the language of the people of Zayla’ [Awdali Somalis].”21
The author’s description about seasons generally corresponds to the local seasons in historical Awdal where Karan or Karam is an important rainy season at the beginning of the year. The second half of the year is called ‘Bilo Dirir’, (Bil = month; Bilo = months). It appears that the historian was referring, in one-way or another, to these still used terms, Karan and Bil. This indicates that the ancient Somali solar calendar was very similar to the one they use today.
Structure.
Besides the weekly cycle, there are four other major cycles in the system: the 50-day cycle, which is 7 weeks + 1 day; the yearly cycle which is 7 x 50 days plus 15 days; the seven-year cycle which is 7 x 365 or 2,555 days long; and the 49-year cycle which is 7 x 7 years in length. All these time units share the number of seven or weekly cycle. Every unit is named after its first day, which is also the last day of yearly and 50-day cycles.
The first 50 days of the Somali Calendar Year of 2007-2008, in the Gregorian system, are from Saturday July 21, 2007, to Saturday Sep. 8, 2007. The same pattern applies to the first and the last days of the year, "while the first day of the year" is Saturday, July 21, 2007, "the last day of the year" is Saturday, July 19, 2008, because this calendar is based on the summer solstices. Thus, the time units used in this year are 50-day intervals and 365-day intervals, and the "name of this year is Saturday". These time units are carefully and systematically enumerated day by day and period by period where practice and redundancy have resulted in sophistication and accuracy.
Year length.
Since the yearly cycle depends on the 50-day and the weekly cycles, these three cycles are primary units of the system. Its length is determined by them. Let us take our Saturday year of 2007-2008 as an example: the first 50 days of this year are also called Saturday period. Consequently, the next 50 days are Sunday period. The remaining periods of the cycles follow the weekdays order. But, "the total of the days in the cycles are 350 or 50 weeks." So that, in order to organize a year, and to allow the succeeding years to follow the order, two weeks and one day must be added to this number which results in 365 days. The following chart shows what we have said in words.
The Months, Days and Seasons of the Somali Calendar.
The Days of the Week.
The beginning of the first season does not exactly fall on ‘Dabshid’, the 1st day of the New Year. Instead, it follows the Gregorian calendar closely in that. The beginnings of the seasons usually fall in the first weeks of July, October, January and April respectively, while the "New Year is around July 20". Despite the fact that the beginnings of the four seasons do not correspond to the beginnings of the New Year and the other months, the two parts are perceived as having a standardized correlation. The disparity is only about two weeks. Additionally, the New Year and Lixkor, the first month of the second dry season, begin when the land becomes completely dry and all types of livestock are due to go to the well. Therefore, apart from this insignificant regress, the adopted months of the year systematically correspond 
to the seasons.
In fact, the meanings of names for the seasons and the months describe the periodic nature of the names themselves. They represent fundamental human needs expressed in practical timekeeping patterns rather than ideological concerns. With the exception of Deyr, the meanings of names of other seasons are not known with certainty because of terminological obsolescence.
Nevertheless, these names are meant to convey the nature of the seasons for which they stand. For example, Xagaa means ‘a partially windy and warm, dry season;’ Jiilaal means ‘a partially cold, very dry season;’ while Gu' means ‘sufficient rainfall’". Deyr, which is derived from the term ‘dayro’ (unfavorable condition), means here ‘less rainfall’," in contrast to the Gu' season. The meanings of all months are known as shown in the following table.
Astronomy.
Although the lunar and solar calendar systems operate separately, they are astronomically interconnected and share many similarities. That is because some periods from both systems are identified by moon 
stations (Manaasil or Fadhiga Dayaxa) which are characterized by "certain stars" (Xiddigo) or "constellations" (group of stars - Urur).
Seasons and lunar cycles.
Because the lunar month consists of 28 days plus one or two days, there are at least 28 visible lunation over four weeks. Moon station or conjunction is observed nightly as the moon sets with a star or constellation. Consequently, the date of a certain day can be figured out by the position of the moon in the horizon. The star or constellation that set with the moon in each of the four weeks of every month is also identified with each of the four seasons in a year. Here, every week in the month corresponds to one quarter of the year.
Configurations associated with the seasons.
1. Xagaa (summer) is marked by Naaf group: Naaf Cadde (white naaf), Naaf Madobe (black naaf), Afqoys, Kuxdin Hore, Kuxdin Dambe, Dirir-day" (semi-dirir), and Dirir".
2. Deyr (autumn) is marked by Dalalle group: Garbo, Gudban, Lib Casse, Hor Dameer, Hor Cadde, Mareega-Dheer, "and Bah."
3. Jiilaal (winter) is marked by Faraci group: Faraci, Listaan, Lixo (the six), Cadcad, Saco (the cows), Nujusi, "and Afa-gaal or Naasa-Gaal" (camel’s breasts)
4. Gu' (spring) is marked by Cirir group: Faruuryo, Jid Gabarre, Jid Gacanle, Jid-Dhiriqle or Dheregle, Rab Hore, Gog Madobe, and Rab Dambe.
Some of the seasons have more than one name. Naasa-gaal, for instance, are also known as Wadaamogoo – "cutting the buckets (of drawing the water from the well)". 
These 28 configurations are not only used 
for timekeeping and weather forecasting, they include extended stars that are used as horizon-marking 
devices. Apart from being held in high regard by the culture, these horizon-marking devices serve as
essential directional guides for nightly journey both by land and sea.
Determining Dirir.
By the Somali standard method of calculation, the year has two divisions. "The first half of the year is called" Bilo Dabshid (Months of Dabshid). In this division, the length of the months is calculated by counting the days from Dabshid, the New Year. "The second half is called" Bilo Dirir (months of Dirir). 
Dirir is a star that is identified with Spica, in the European astronomy, which is used by both the two Somali calendars to interconnect some of their operations in a particular conjunction. As a result, the conjunction is astrologically calculable and observable by the lulation or "average time for one lunar phase cycle." The occurrence of the star rising with a particular moon phase is also called Dirir. 
Thus, Dirir is a monthly conjunction in which the lunar phase changes but its position in the sky is held constant.
The dates of Dirir in solar months are of not much concern because almost everything is held constant. The Dirir months in the "lunar system" naturally shift, but a Dirir date in a given month is one of three particular days, depending on the length of the month, 29 or 30 days, so it is almost held constant. For this reason, "the first" Dirir, Lixkor, "falls on the 21st, 20th, or 19th of the lunar month", "forcing each Dirir to occur two days later than the preceding one in the next month". For example, suppose that Lixkor "falls on the 20th of seventh lunar month", Rajab; "the next Dirir, Toddob, "will take place on the 18th of the following month", Sha’baan; "while the sixth Dirir, Samuulaad, "will fall on the 10th of twelfth month", Dul-Hijjah.
The event standardizes the beginning and the length of the solar month as well as designates the rainfall periods in the second half of the year. Right after the conjunction, there is usually rain or at least a sign of rain, depending on the fasal or season. Further, this lunisolar interconnection permits a layman to observe the Dirir in night. "Since the lunar year is approximately ten days shorter than the solar year", the lunar year annually begins about ten days earlier than the last year’s correspondence date. For this reason, the beginning of the lunar year and other important dates can also be estimated by ordinary observers. This gives them another way of calculating the correspondences between the two systems. Although Dirir "lasts for six months", a nominal Dirir, Dirir-Sagaar, is recognized to satisfy the rule of ‘seven’. Dirir-Sagaar occurs prior to the "eve of" Dabshid, which shows its lack of Dirir requirements. Some say that it is not Dirir, but part of Samuulad.