Daniel Collins was born August 1, 1834 and Hannah (Sullivan) Collins was born in April, 1835. Daniel was 13, and Hannah was 12 when the potato famine broke out across Ireland. Both Daniel and Hannah were originally from County Cork, Ireland. The couple met in Ireland, however it is unknown whether they married before or after arriving in America.

Hannah immigrated to the United States in 1855, during the mass immigration to America as a result of the potato famine. Compared with other counties in Ireland, County Cork had high rates of poverty and people seeking a better life. As a result, Cork saw much more emigration than other counties of Ireland. Daniel immigrated to the United States sometime prior to 1860, and became a naturalized U.S. citizen in June, 1872.