William IV (c. 1030 – 1100) was the fifth

Marquis of Montferrat The Marquises and Dukes of Montferrat were the rulers of a territory in Piedmont south of the Po and east of Turin called Montferrat. The March of Montferrat was created by Berengar II of Italy in 950 during a redistribution of power in the no ...

from 1084. The date of William's birth is unknown, but it most likely took place between 1030 and 1035. He was the eldest son of

Otto II Otto II (955 – 7 December 983), called the Red (''der Rote''), was Holy Roman Emperor from 973 until his death in 983. A member of the Ottonian dynasty, Otto II was the youngest and sole surviving son of Otto the Great and Adelaide of Italy. ...

and Constance of Savoy.

Life

He first appears in a document of 1059, when he is placed in power over the city of

Savona Savona (; lij, Sann-a ) is a seaport and ''comune'' in the west part of the northern Italy, Italian region of Liguria, capital of the Province of Savona, in the Riviera di Ponente on the Mediterranean Sea. Savona used to be one of the chie ...

, probably as per a request of the citizenry for a ruler of their own. He was present when the

Emperor Henry IV Henry IV (german: Heinrich IV; 11 November 1050 – 7 August 1106) was Holy Roman Emperor from 1084 to 1105, King of Germany from 1054 to 1105, King of Italy and Burgundy from 1056 to 1105, and Duke of Bavaria from 1052 to 1054. He was the son ...

donated the monastery of

Breme Breme (Lombard language, Lombard: ''Bräm'') is a ''comune'' (municipality) in the Province of Pavia in the Italy, Italian region Lombardy, located about southwest of Milan and about west of Pavia. As of 31 December 2004, it had a population of 8 ...

to the church of

Pavia Pavia (, , , ; la, Ticinum; Medieval Latin: ) is a town and comune of south-western Lombardy in northern Italy, south of Milan on the lower Ticino river near its confluence with the Po. It has a population of c. 73,086. The city was the capit ...

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In an act dated 15 September 1096, ''Uvilielmus marchio filius quondam Uvilielmi et Ota iugalis eius filia quondam Tebaldi et Uvilielmus filius presicti Uvilielmi et Ote, et Oto filius item Otonis, seu Petrus filius Roberti, atque coniunx eius Ermengarda filia predicti Tebaldi et Tezo filius iamdicti Petri et Ermengarde'' conceded their rights over the church of

Santo Stefano di Allein Santo ('saint' in various languages) may refer to: People * Santo (given name) * Santo (surname) * El Santo, Rodolfo Guzmán Huerta (1917–1984), Mexican wrestler and actor * Bob Santo or Santo, stage name of Ghanaian comedian John Evans Kwadwo ...

. By his second marriage with Otta di Aglié, William was the father of his successor Rainier. He had two children by his first marriage, but their fate is unknown.

Sources

*Caravale, Mario (ed). ''Dizionario Biografico degli Italiani: LX Grosso – Guglielmo da Forlì''. Rome, 2003.
Marchesi di Monferrato: Guglielmo IV.
{{DEFAULTSORT:William 04 of Montferrat 1030s births 1100 deaths Marquesses of Montferrat 11th-century Italian nobility Aleramici Year of birth uncertain