Alexander Morrison (1808-1853) was born in Westmoreland County, Pennsylvania. His ancestors are believed to have immigrated from Northern Ireland. Alexander's father was probably Daniel Morrison, listed in the 1810 census of Salem Township, Westmoreland County (who names a son Alexander in his will). However, there were three other Morrison families who lived in Westmoreland County in 1810 and had a son under ten years of age. The heads of household of the three other eligible Morrison families were Agnes Morrison (Salem Township), John Morrison (Union Township) and Robert Morrison (Mount Pleasant Township). Of the four potential families, it is believed that Alexander was born to either Daniel or Agnes, as Alexander eventually married in Salem Township.