He wrote a translation of the Bible into Latin with Emmanuel Tremellius, and his Treatise on True Theology (De Vera Theologia) was an often used text in Reformed scholasticism.
Franciscus Junius was born in Bourges, and beginning at age twelve studied law at the university there under François Douaren and Hugo Donellus.
[4] He went in 1562 to study at Geneva under John Calvin and Theodore Beza, where he was reduced to poverty by the failure of remittances from home, owing to civil war in France.
The long-expected remittance from home was closely followed by the news of the brutal murder of his father by a Catholic fanatic at Issoudun; and Junius resolved to remain at Geneva, where his reputation enabled him to live by teaching.
[5] William the Silent made an agreement with Philip II of Spain in 1566 to protect Protestants, but only those who were natives of the Low Countries, placing Junius in danger.
There he was welcomed by the elector Frederick II, and temporarily settled in charge of the Reformed church at Schönau; but in 1568 his patron sent him as chaplain with Prince William of Orange in his unfortunate expedition to the Netherlands.
[3] From 1573 till 1578 he was at Heidelberg, assisting Emmanuel Tremellius,[3] whose daughter he married; their child, also called Franciscus Junius, became an early scholar of Germanic philology.
[8][9] Frederick III was succeeded by Louis IV, a Lutheran, in 1576, and the Reformed in Heidelberg who refused to sign the Formula of Concord were forced out.