William Aleyn was a 15th century English pirate. During the 1430s and 40s, he raided shipping throughout Southeast England and sometimes worked with William Kyd

William Kyd

William Kyd was a 15th century English pirate active in Southwest England from the 1430s until the 1450s. He and others, such as John Mixtow, William Aleyn and Clays Stephen, acted under virtual immunity from the law for over two decades while under the protection of corrupt custom...

 in the Thames and the English Channel

English Channel

The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...

. Like others of his trade, Aleyn operated freely and without interference from authorities while under the protection of corrupt custom officials.

Biography

In 1431, Aleyn was listed as one of several pirates active in the area according to a public document published that year. He joined William Kyd

William Kyd

William Kyd was a 15th century English pirate active in Southwest England from the 1430s until the 1450s. He and others, such as John Mixtow, William Aleyn and Clays Stephen, acted under virtual immunity from the law for over two decades while under the protection of corrupt custom...

 and several others in capturing four ships carrying provisions bound for Rouen

Rouen

Rouen , in northern France on the River Seine, is the capital of the Haute-Normandie region and the historic capital city of Normandy. Once one of the largest and most prosperous cities of medieval Europe , it was the seat of the Exchequer of Normandy in the Middle Ages...

 in 1433. Fifteen years later, he and Kyd began seizing ships in the assisted him in seizing ships in the Thames and carrying them down to the English Channel

English Channel

The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...

. He was particularly active near Thanet

Thanet

Thanet is a local government district of Kent, England which was formed under the Local Government Act 1972, and came into being on 1 April 1974...

, although no more is heard of him after this time.