In 1880, he was promoted to Major and in 1882 he worked as an assistant to the National Astronomical Observatory at the Equatorial Telescope to study the transit of Venus and in the following year, he was appointed a member of the commission that was in charge of discussing the Statistical Regulations.

In 1910 and 1911 he fought the Maderistas in Chihuahua, and after the fall of the Porfiriato he was promoted to brigadier general on September 12, 1911, by agreement of the interim president Francisco León de la Barra.

In February 1912 he was commissioned to organize an Auxiliary Irregular Battalion of the Federation in Jalapa and Veracruz and on March 5 received from Francisco I. Madero the Secretary of War and Navy in his presidential cabinet.

When the events known as the Ten Tragic Days unleashed, García Peña faced the uprising and on February 9, he attempted to evict a group of rebels who were in the National Palace, but was wounded during the fighting as he was shot through the arm.

At that time, García Peña dedicated himself to carrying out private surveying works, but when in April 1914 the government of Huerta sent for him on the notice of the United States occupation of Veracruz, he immediately left in command of a division of five thousand men heading for Perote in order to fight the Americans but was defeated in the battle.