Dictionary of Medieval Names
from European Sources

Isaac m. Hebrew יִצְחָק '[he] will laugh'.

The name of a Biblical patriarch. Wycliffite Bible (1395): Isaac. Sagradas Escrituras (1569): Isaac.

England
Latin
1222 Ysaac (nom) StPaulDom p. 101; 1279–80 Isak (nom) WaHR-SK p. 36
Dutch
1572 Isaac AuFr Bontenaken, Isaack ibid. Bogarts; 1574 Isaack ibid. Costere, Isack ibid. Dierecksen; 1576 Isaac ibid. Assendelft, Isaack ibid. Clerx; 1579 Isaac ibid. Engelgrave; 1581 Isaac ibid. Gast; 1583 Isaac ibid. Engelgrave; 1584 Isaac ibid. Brauwers; 1587 Isaac ibid. Brugge, Isaak ibid. Bogaerts; 1590 Isaack ibid. Cleijmans; 1591 Isaac ibid. Beun; 1592 Isaac ibid. Buen; 1593 Isaac ibid. Alaerts; 1594 Isaack ibid. Baert; 1596 Isaac ibid. Connick; 1597 Isaac ibid. Freschner; 1599 Isaac ibid. Clerck
Walloon
1581/2 Isaac RWC p. 4; 1582 Isaac ibid. p. 4; 1582/3 Isaac ibid. p. 5; 1583/4 Isaac ibid. p. 437; 1583 Isaac ibid. p. 6; 1584 Isaac ibid. p. 437; 1591/2 Isaac ibid. p. 563
Finland
Early Modern Swedish
1582 Isack (nom) Audén1980 p. 171
France
Latin
1378 Ysaco (dat) hanquetvol1 1169
Middle French
1562 Isaac RegPCC-1 p. 14; 1563 Isaac ibid. p. 24; 1564 Isaac ibid. p. 55, Ysaac ibid. p. 90; 1565 Isaac ibid. p. 189, Ysaac ibid. p. 163; 1566 Isaac ibid. p. 215, Ysaac ibid. p. 218; 1567 Isaac ibid. p. 292, Ysaac ibid. p. 328; 1568 Isaac ibid. p. 373, Ysaac ibid. p. 374; 1570 Isaac ibid. p. 426; 1571 Isaac ibid. p. 482; 1572 Esaac ibid. p. 514, Isaac ibid. p. 517
Germany
Latin
891 Ysaac (nom) UrkStyria 10
Hungary
Latin
1323 Isaak Slíz p. 173, s.n. Isaak; 1330 Isaak ibid. p. 173, s.n. Isaak; 1331 Isak ibid. p. 173, s.n. Isaak; 1332x1337 Ysaak (nom) ibid. p. 173, s.n. Isaak; 1341 Isaak ibid. p. 173, s.n. Isaak
Ireland
Latin
fin12thC Isaac (nom) MunDocIr III, p. 17
Italy
Latin
1237 Ysaki (gen) TirNot1 584; 1527 Jsach (nom) Rome1527 p. 87
1285 Ysacutii (gen) Perugia1285 p. 154
Scotland
Latin
1238 Ysaaco (abl) CartLevenax p. 13
Sweden
Old Swedish
1419 Ysaak (nom) SDHK no. 19242, Ysak (gen) ibid. no. 19242
Switzerland
Latin
1188 Ysaac (nom) CartHaut 28
Cite as: R. Le Get, M. Slíz, S.L. Uckelman. "Isaac". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2018, no. 1. http://dmnes.org/2018/1/name/Isaac.