Carolus Masius
Bishop of Ghent
Province	Mechelen
Diocese	Ghent
See	St Bavo's
Installed	1610
Term ended	1612
Predecessor	Pieter Damant
Successor	Franciscus van der Burch
Previous post(s)	Bishop of Ypres
Orders
Consecration	24 June 1607
Personal details
Born	1559 Brussels, Duchy of Brabant, Habsburg Netherlands
Died	21 May 1612 Ghent, County of Flanders, Habsburg Netherlands
Buried	Crypt of St Bavo's Cathedral, Ghent
Denomination	Roman Catholic
Parents	Jacobus Maes and Aleyde de Tassis
Motto	Deo duce
Coat of arms

Karel Maes, Latinized Carolus Masius (1559–1612) was bishop of Ypres and later bishop of Ghent in the Habsburg Netherlands.^[1]

Maes was born in Brussels in 1559, the son of Jacobus Maes, a member of the Council of Brabant, and Aleyde de Tassis. He received holy orders and on 10 May 1590 was appointed dean of Antwerp Cathedral. He went on to become grand almoner to the Archdukes Albert and Isabella.^[2]

He was consecrated bishop of Ypres on 24 June 1607, in succession to Petrus Simons.^[2] This was the beginning of a period of peace (due to the ceasefire preceding the Twelve Years' Truce of 1609–1621) and of rebuilding after the devastations of the Dutch Revolt.

After Pieter Damant's death he was transferred to the diocese of Ghent, taking possession of the see on 5 November 1610. In 1611 he co-consecrated Johannes Malderus as bishop of Antwerp.^[2] His notable exertions to restore order to his diocese undermined his health, and he died in Ghent on 21 May 1612.^[2] Canon Antoine De Smet delivered his eulogy. His main legatee was Marguerite Maes, but he also left a number of relics to his cathedral.^[2] He was buried in the cathedral crypt. His monument was damaged in 1666, and a new one designed by Rombaut Pauwels was erected in the choir.^[2]