Segwarides is a Knight of the Round Table

Round Table (Camelot)

The Round Table is King Arthur's famed table in the Arthurian legend, around which he and his Knights congregate. As its name suggests, it has no head, implying that everyone who sits there has equal status. The table was first described in 1155 by Wace, who relied on previous depictions of...

 in the Arthurian legend. In the Prose Tristan

Prose Tristan

The Prose Tristan is an adaptation of the Tristan and Iseult story into a long prose romance, and the first to tie the subject entirely into the arc of the Arthurian legend...

 and Sir Thomas Malory

Thomas Malory

Sir Thomas Malory was an English writer, the author or compiler of Le Morte d'Arthur. The antiquary John Leland as well as John Bale believed him to be Welsh, but most modern scholars, beginning with G. L...

's Le Morte d'Arthur

Le Morte d'Arthur

Le Morte d'Arthur is a compilation by Sir Thomas Malory of Romance tales about the legendary King Arthur, Guinevere, Lancelot, and the Knights of the Round Table...

, Segwarides is a liegeman of King Mark who is cuckholded by Tristan

Tristan

Tristan is one of the main characters of the Tristan and Iseult story, a Cornish hero and one of the Knights of the Round Table featuring in the Matter of Britain...

. Malory also lists an individual of this name as a son of the Saracen

Saracen

Saracen was a term used by the ancient Romans to refer to a people who lived in desert areas in and around the Roman province of Arabia, and who were distinguished from Arabs. In Europe during the Middle Ages the term was expanded to include Arabs, and then all who professed the religion of Islam...

 king Esclabor

Esclabor

Esclabor is a lord of Babylon and father of Palamedes, Safir, and Segwarides in Arthurian Legend. While visiting Rome, he saves the life of its emperor and then goes to Logres where he saves the life of King Pellinore. He eventually retires to Camelot....

; his brothers are Palamedes

Palamedes (Arthurian legend)

Palamedes is a Knight of the Round Table in the Arthurian legend. He is a Saracen pagan who converts to Christianity later in his life, and his unrequited love for Iseult brings him into frequent conflict with Tristan...

 and Safir. It seems there were originally two characters of this name, but the stories in which they appear fail to differentiate between them.

In Malory, Tristan has a brief affair with Segwarides' wife, and wounds the knight after being found out. Tristan encounters Segwarides later on the Isle of Servage. Segwardies forgives the more famous knight saying he "will never hate a noble knight for a light lady", and the two team up to avoid the dangers of the isle. Soon afterwards Tristan makes Segwarides Lord of Servage.

Sir Segwarides is killed trying to repel Sir Launcelot's rescue of Guinevere

Guinevere

Guinevere was the legendary queen consort of King Arthur. In tales and folklore, she was said to have had a love affair with Arthur's chief knight Sir Lancelot...

from the stake.