John I was the Margrave of Montferrat, last the Aleramici dynasty, from 1292 to his death.

John was the only son of William VII of Montferrat and his second wife Beatrice

Beatrice of Castile, Marchioness of Montferrat

Beatrice of Castile was a daughter of Alfonso X of Castile and his wife Violant of Aragon. She was Marchioness of Montferrat by her marriage and was mother of Irene of Montferrat.- Family :...

, daughter of Alfonso X of Castile

Alfonso X of Castile

Alfonso X was a Castilian monarch who ruled as the King of Castile, León and Galicia from 1252 until his death...

. In his youth, John was put under the tutelage of Thomas I of Saluzzo

Thomas I of Saluzzo

-Life and Reign:Thomas I was the fourth marquess of Saluzzo from 1244 to his death. He succeeded his father Manfred III. Under the reign of Thomas, Saluzzo blossomed, achieving a greatness which had eluded his ancestors. He crafted a state the borders of which remained unchanged for over two...

 during the period of William's imprisonment in Alessandria

Alessandria

-Monuments:* The Citadel * The church of Santa Maria di Castello * The church of Santa Maria del Carmine * Palazzo Ghilini * Università del Piemonte Orientale-Museums:* The Marengo Battle Museum...

. William died in prison and the peace was upset by Piedmont

Piedmont

Piedmont is one of the 20 regions of Italy. It has an area of 25,402 square kilometres and a population of about 4.4 million. The capital of Piedmont is Turin. The main local language is Piedmontese. Occitan is also spoken by a minority in the Occitan Valleys situated in the Provinces of...

ese rebellions. Charles II of Naples

Charles II of Naples

Charles II, known as "the Lame" was King of Naples, King of Albania, Prince of Salerno, Prince of Achaea and Count of Anjou.-Biography:...

 interevened for the defence of John's realm, hoping in the end to install him as his vassal in Piedmont.

With Charles and Thomas, who renewed the investiture of Dogliani

Dogliani

Dogliani is a comune in the Province of Cuneo in the Italian region Piedmont, located about 60 km southeast of Turin and about 35 km northeast of Cuneo....

, John fought against Alessandria and Asti

Asti

Asti is a city and comune of about 75,000 inhabitants located in the Piedmont region of northwestern Italy, about 55 kilometres east of Turin in the plain of the Tanaro River...

 to recuperate territories lost by his father. He came in conflict with the House of Savoy

House of Savoy

The House of Savoy was formed in the early 11th century in the historical Savoy region. Through gradual expansion, it grew from ruling a small county in that region to eventually rule the Kingdom of Italy from 1861 until the end of World War II, king of Croatia and King of Armenia...

 and Milan

Milan

Milan is the second-largest city in Italy and the capital city of the region of Lombardy and of the province of Milan. The city proper has a population of about 1.3 million, while its urban area, roughly coinciding with its administrative province and the bordering Province of Monza and Brianza ,...

. Philip of Savoy

Philip of Savoy

Philip I, known as Philip of Savoy was the lord of Piedmont from 1282 until his death and prince of Achaea between 1301 and 1307. He was the son of Thomas III of Piedmont and Guyonne de Châlon....

 possessed Collegno

Collegno

Collegno is a comune in the Province of Turin in the Italian region Piedmont, located about 9 km west of Turin.-Twin towns — Sister cities:Collegno is twinned with the following cities:-External links:*...

, Grugliasco

Grugliasco

Grugliasco is a comune in the Province of Turin in the Italian region Piedmont, located about 9 km west of Turin.Grugliasco borders the following municipalities: Turin, Collegno, and Rivoli.-External links:*...

, Turin

Turin

Turin is a city and major business and cultural centre in northern Italy, capital of the Piedmont region, located mainly on the left bank of the Po River and surrounded by the Alpine arch. The population of the city proper is 909,193 while the population of the urban area is estimated by Eurostat...

, and Pianezza

Pianezza

Pianezza is a comune in the Province of Turin in the Italian region Piedmont, located about 12 km northwest of Turin.-External links:*...

 which had been lost by William VII. The league John formed against Matteo Visconti succeeded in chasing him from the city in 1302 and obtaining the submission of Asti in 1303. In January 1305, he fell ill while planning a campaign against Savoy. A few days after dictating his testament, which entrusted his lands to the commune

Medieval commune

Medieval communes in the European Middle Ages had sworn allegiances of mutual defense among the citizens of a town or city. They took many forms, and varied widely in organization and makeup. Communes are first recorded in the late 11th and early 12th centuries, thereafter becoming a widespread...

 of Pavia

Pavia

Pavia , the ancient Ticinum, is a town and comune of south-western Lombardy, northern Italy, 35 km south of Milan on the lower Ticino river near its confluence with the Po. It is the capital of the province of Pavia. It has a population of c. 71,000...

, he died and was buried with his forefathers in the abbey of Santa Maria di Lucedio.