The exiles in Hong Kong organized a Supreme Council, electing del Pilar to a position second only to Tomás Mascardo.
Aguinaldo's confidence in del Pilar grew such that he wrote the following about him:
"I took him to Hong Kong, Saigon, and Singapore.
He was my man of confidence.
I could trust him with everything.
Therefore, I had him always at my side until he died."

— Emilio Aguinaldo
When Aguinaldo was supposed to go to Europe, he took only del Pilar and Colonel José Leyba with him.
The trip ended in Singapore, where Aguinaldo conferred with American consul E. Spencer Pratt, learning of the American declaration of war against Spain.
Spurred by this, Aguinaldo and the other exiles decided to return to the Philippines to restart the revolution.

After the Americans defeated the Spanish in the Battle of Manila Bay, Aguinaldo, del Pilar, and other exiled leaders returned to the Philippines.
Aguinaldo named del Pilar Dictator of Bulacan and Nueva Ecija provinces, an honor Aguinaldo would not confer to anybody else.

On del Pilar's return to the Philippines, he set out to liberating his home province of Bulacan, eventually accepting Spanish surrender on June 24, 1898.
Del Pilar was then called to relieve the wounded General Pantaleon García and continue operations in Caloocan, ultimately succeeded on August 13, 1898.
The Revolutionary Congress was then inaugurated on September 15, 1898 and del Pilar became in charge of the military parade.
He was promoted to brigadier-general after this event.

When the Philippine-American War broke out in February 1899, following the cession of the Philippines by Spain to the United States in the Treaty of Paris of 1898, del Pilar fought alongside General Antonio Luna in Manila, suffering heavy casualties.
Del Pilar's relationships with his fellow generals were contentious at best.
General José Alejandrino wrote of del Pilar:
"There was a young pretentious general who set up his headquarters in one of the nearby towns, not bothering even to present himself to General [Antonio] Luna.
He did not want to recognize any orders other than those which emanated directly from the Captain General [Emílio Aguinaldo] of whom he was a great favorite.
At the headquarters of General Luna it was learned that his gentleman spent days and nights at fiestas and dances which his flatterers offered in his honor."

— Jose Alejandrino
Another story between Luna and del Pilar have the two riding together on the front, with Luna so absorbed in what he was saying that he did not notice they were moving into a danger zone.
Del Pilar did notice but did not back off because Luna had not.
After Manila, del Pilar and his troops moved to Bulacan.
Major General Venancio Concepción was placed under his command but the two did not get along.
After the fall of Baliuag each blamed the other.
Concepción was eventually moved under the command of Luna in Pampanga.
Del Pilar, for his part, led his troops to a victory over Major Franklin Bell in the first phase of the Battle of Quingua (modern-day Plaridel, Bulacan) on April 23, 1899.
During the battle, his forces repelled a cavalry charge and killed American Colonel John M. Stotsenburg,.
The Americans were, however, reinforced during the second phase of the Battle and the Filipino forces were forced to retreat.
Del Pilar then participated in the Battle of Calumpit alongside General Luna.
Luna, however, had left the battle to punish General Tomás Mascardo for insubordination, leaving del Pilar with the defense of the Bagbag river.
On Luna's return, the Americans had already succeeded in penetrating the Filipino lines and they were forced to retreat.

On June 4, 1899, del Pilar joined Aguinaldo in San Isidro, Nueva Ecija and received orders to capture Antonio Luna, dead or alive, on charges of high treason.
It is said that had Luna not come down himself to Cabanatuan and assassinated by the Kawit Batallion from his headquarters in Bayambang that del Pilar would have gone down as Luna's killer.
Del Pilar and Aguinaldo then descended upon General Concepcion's headquarters in Pampanga to re
The exiles in Hong Kong organized a Supreme Council, electing del Pilar to a position second only to Tomás Mascardo. Aguinaldo's confidence in del Pilar grew such that he wrote the following about him:
"I took him to Hong Kong, Saigon, and Singapore. He was my man of confidence. I could trust him with everything. Therefore, I had him always at my side until he died."
— Emilio Aguinaldo
When Aguinaldo was supposed to go to Europe, he took only del Pilar and Colonel José Leyba with him. The trip ended in Singapore, where Aguinaldo conferred with American consul E. Spencer Pratt, learning of the American declaration of war against Spain. Spurred by this, Aguinaldo and the other exiles decided to return to the Philippines to restart the revolution.
After the Americans defeated the Spanish in the Battle of Manila Bay, Aguinaldo, del Pilar, and other exiled leaders returned to the Philippines. Aguinaldo named del Pilar Dictator of Bulacan and Nueva Ecija provinces, an honor Aguinaldo would not confer to anybody else.
On del Pilar's return to the Philippines, he set out to liberating his home province of Bulacan, eventually accepting Spanish surrender on June 24, 1898. Del Pilar was then called to relieve the wounded General Pantaleon García and continue operations in Caloocan, ultimately succeeded on August 13, 1898. The Revolutionary Congress was then inaugurated on September 15, 1898 and del Pilar became in charge of the military parade. He was promoted to brigadier-general after this event.
When the Philippine-American War broke out in February 1899, following the cession of the Philippines by Spain to the United States in the Treaty of Paris of 1898, del Pilar fought alongside General Antonio Luna in Manila, suffering heavy casualties. Del Pilar's relationships with his fellow generals were contentious at best. General José Alejandrino wrote of del Pilar:
"There was a young pretentious general who set up his headquarters in one of the nearby towns, not bothering even to present himself to General [Antonio] Luna. He did not want to recognize any orders other than those which emanated directly from the Captain General [Emílio Aguinaldo] of whom he was a great favorite. At the headquarters of General Luna it was learned that his gentleman spent days and nights at fiestas and dances which his flatterers offered in his honor."
— Jose Alejandrino
Another story between Luna and del Pilar have the two riding together on the front, with Luna so absorbed in what he was saying that he did not notice they were moving into a danger zone. Del Pilar did notice but did not back off because Luna had not. After Manila, del Pilar and his troops moved to Bulacan. Major General Venancio Concepción was placed under his command but the two did not get along. After the fall of Baliuag each blamed the other. Concepción was eventually moved under the command of Luna in Pampanga. Del Pilar, for his part, led his troops to a victory over Major Franklin Bell in the first phase of the Battle of Quingua (modern-day Plaridel, Bulacan) on April 23, 1899. During the battle, his forces repelled a cavalry charge and killed American Colonel John M. Stotsenburg,. The Americans were, however, reinforced during the second phase of the Battle and the Filipino forces were forced to retreat. Del Pilar then participated in the Battle of Calumpit alongside General Luna. Luna, however, had left the battle to punish General Tomás Mascardo for insubordination, leaving del Pilar with the defense of the Bagbag river. On Luna's return, the Americans had already succeeded in penetrating the Filipino lines and they were forced to retreat.
On June 4, 1899, del Pilar joined Aguinaldo in San Isidro, Nueva Ecija and received orders to capture Antonio Luna, dead or alive, on charges of high treason. It is said that had Luna not come down himself to Cabanatuan and assassinated by the Kawit Batallion from his headquarters in Bayambang that del Pilar would have gone down as Luna's killer. Del Pilar and Aguinaldo then descended upon General Concepcion's headquarters in Pampanga to re
Gregorio del Pilar