Andrianampoinimerina was born Ramboasalamarazaka (short form: Ramboasalama) around 1745 in Ikaloy, in central Madagascar, to Princess Ranavalonandriambelomasina, daughter of King Andriambelomasina of Imerina (1730-1770), and her husband Andriamiaramanjaka, an andriana (noble) of the Zafimamy royal family in the independent kingdom of Alahamadintany to the north of Imerina.
Ramboasalamarazaka spent his early childhood in his father's Zafimamy court at Ikaloy.