De Catholicis seu Patriarchis Chaldaeorum et Nestorianorum Commentarius Historico-Chronologicus, originally published in Rome in 1775, remains the major reference to the history of the Patriarchs of the Church of the East (Chaldean and "Nestorian"). Its author, Josephus Aloysius Assemani (1710-1782), was the brother of the illustrious Joseph Assemani. The volume is appended by another work by J.A. Assemani on church unity.Josephus Aloysius Assemani (1710-1782) was born in Tripoli, Lebanon. He made his theological and Oriental studies in Rome and under the care of his brother Joseph Assemani. He was appointed by the Pope, first, as professor of Syriac at the Sapienza in Rome, and afterwards professor of liturgy, by Benedict XIV, who made him also member of the academy for historic research, just founded.