His father, a former Colonel in the Army of the Andes, had settled in Chile from Argentina and was a grandson of Patrick Lynch, an emigrant from Galway to Buenos Aires in the 1740s.
[2] Entering the navy in 1837, at the age of 12, he took part in the Battle of Socabaya in 1838, during the War of the Confederation that led to the fall of Marshal Andrés de Santa Cruz.
The Chincha Islands War saw him again employed, and he was successively maritime Prefect of Valparaiso, colonel of National Guards, and finally captain and minister of marine in 1872.
In early September 1880, he led a raid against northern Peru to gather ransom payments from business and sugar plantation owners, that has become known as the "Lynch Expedition".
The Chinese also fought alongside the Chileans in the battles of San Juan-Chorrillis and Miraflores, and there was also rioting and looting by non-Chinese workers in the coastal cities.
As Heraclio Bonilla has observed; oligarchs soon came to fear the popular clashes more than the Chileans, and this was an important reason why they sued for peace".