Walter Oswald Watt was born in 1878 in Bournemouth, England.
His father was John Brown Watt, a merchant and a Member of the New South Wales Legislative Council, and his mother was Mary Jane Watt (née Holden), who died when he was a baby.
Walter Watt spent the first ten years of his life in Sydney and was sent then to be educated in England at Clifton College, Bristol, and Trinity College, Cambridge where he obtained his Bachelor and Master of Arts degrees.
Watt returned to Sydney in 1900 and became second lieutenant in the New South Wales Scottish Rifles and in 1902 was appointed aide-de-camp to the Governor of New South Wales.

In 1902 Watt married Muriel Maud Williams, the daughter of Sir Hartley Williams, a Justice of the Supreme Court of Victoria, and Edith Ellen Williams (née Horne).
The couple bought Wivenhoe in 1905 and in the same year had their only child, James.
They owned the property until 1910 when they sold it to the Sisters of the Good Samaritan.

In 1914, at the outbreak of World War I, Walter joined the French Foreign Legion and was awarded two military honours.
In 1916 he transferred to the newly formed Australian Flying Corps and served there as captain.
Walter Oswald Watt was born in 1878 in Bournemouth, England. His father was John Brown Watt, a merchant and a Member of the New South Wales Legislative Council, and his mother was Mary Jane Watt (née Holden), who died when he was a baby. Walter Watt spent the first ten years of his life in Sydney and was sent then to be educated in England at Clifton College, Bristol, and Trinity College, Cambridge where he obtained his Bachelor and Master of Arts degrees. Watt returned to Sydney in 1900 and became second lieutenant in the New South Wales Scottish Rifles and in 1902 was appointed aide-de-camp to the Governor of New South Wales.
In 1902 Watt married Muriel Maud Williams, the daughter of Sir Hartley Williams, a Justice of the Supreme Court of Victoria, and Edith Ellen Williams (née Horne). The couple bought Wivenhoe in 1905 and in the same year had their only child, James. They owned the property until 1910 when they sold it to the Sisters of the Good Samaritan.
In 1914, at the outbreak of World War I, Walter joined the French Foreign Legion and was awarded two military honours. In 1916 he transferred to the newly formed Australian Flying Corps and served there as captain.
Wivenhoe, Narellan