According to Paavali juusien's chronicle of bishops, Agricola was born "in Torsby village in the parish of Perna (Pcrnaja) in lower Nyland". The family estate, listed as Number 1 in the Torsby land register, was later named "Sigh-ids' after Agricolas nephew Sigfrid Minsson, who died in 1634. The farmstead was so wealthy that it was possible to hold district court sessions in the house.
The date of Agricolas birth is unknown, but his later history would place it at around 1510. His father was called Olavi, or Olof in Swedish; his mother’s name is unknown. Olavi appears to have died in the early 1540s, leaving a widow and four adult children: Mikael and three daughters whose names are not mentioned in documents. Agricolas mother died in about 1 550. Afterwards the bailiff of Savonlinna, Clemets Krook, who had married the eldest daughter, sold his share of the inheritance to Mikael. The estate was managed first by Thomas Larsson, the husband of the middle sister, and then, after his death in 1572, by the husband of the youngest sister, Mans Jonsson, whose son Sigfrid inherired it in 1592.