Guy II de la Roche was the Duke of Athens from 1287, the last duke of his family. He succeeded as a minor on the death of his father, William I, at a time when the duchy of Athens had exceeded the Principality of Achaea

Principality of Achaea

The Principality of Achaea or of the Morea was one of the three vassal states of the Latin Empire which replaced the Byzantine Empire after the capture of Constantinople during the Fourth Crusade. It became a vassal of the Kingdom of Thessalonica, along with the Duchy of Athens, until Thessalonica...

 in wealth, power, and importance.

Guy was originally under the tutorship and regency of his mother, Helena Angelina Komnene, who was forced to make submission to Isabella of Villehardouin

Isabella of Villehardouin

Isabella of Villehardouin was the elder daughter of William II of Villehardouin, Prince of Achaea, and of his second wife Anna, the third daughter of Michael II Komnenos Doukas, the despot of Epiros....

 in December 1289. In 1291, she married her second husband, Hugh of Brienne

Hugh of Brienne

Hugh de Candie, Count of Brienne and Lecce was the second surviving son of Count Walter IV of Brienne and Marie de Lusignan of Cyprus....

, and he became bailiff

Bailiff

A bailiff is a governor or custodian ; a legal officer to whom some degree of authority, care or jurisdiction is committed...

 of the duchy. Guy reached his majority in 1296 and did homage to Isabella and her husband, Florent of Hainaut

Florent of Hainaut

Florent of Hainaut was Prince of Achaea from 1289 to his death, in right of his wife, Isabella of Villehardouin. He was the son of John I of Avesnes and Adelaide of Holland...

. In 1299, Guy was engaged to Matilda

Matilda of Hainaut

Matilda of Hainaut was the Princess of Achaea from 1313 to 1318.From 1307, when Philip of Savoy relinquished his claim, to 1312, when Isabella of Villehardouin died, Achaea was disputed between two claimants: Isabella and Philip I of Taranto. In 1313, Philip granted it to Matilda, daughter of...

, daughter of Isabella and Florent. Charles objected, as his permission had not been sought, but Pope Boniface VIII

Pope Boniface VIII

Pope Boniface VIII , born Benedetto Gaetani, was Pope of the Catholic Church from 1294 to 1303. Today, Boniface VIII is probably best remembered for his feuds with Dante, who placed him in the Eighth circle of Hell in his Divina Commedia, among the Simonists.- Biography :Gaetani was born in 1235 in...

 intervened on the young couple's behalf.

When Guy did homage to Isabella's second husband, Philip of Savoy, in 1301, he took his troops with him and entered Thessaly

Thessaly

Thessaly is a traditional geographical region and an administrative region of Greece, comprising most of the ancient region of the same name. Before the Greek Dark Ages, Thessaly was known as Aeolia, and appears thus in Homer's Odyssey....

 to defend his cousin John II Doukas

John II Doukas

John II Doukas, also Angelos Doukas or Angelus Ducas , was ruler of Thessaly from 1303 to his death in 1318....

 against the invasion of the despot of Epirus, Thomas I Komnenos Doukas

Thomas I Komnenos Doukas

Thomas I Komnenos Doukas ruler of Epirus from c. 1297 until his death in 1318.Thomas was the son of Nikephoros I Komnenos Doukas and Anna Kantakouzene, a niece of Emperor Michael VIII Palaiologos. In 1290 he was conferred the court dignity of despotes by his mother's cousin, Emperor Andronikos...

, and his mother, Anna Kantakouzene. Joined by Nicholas III of St Omer, lord of Thebes

Thebes, Greece

Thebes is a city in Greece, situated to the north of the Cithaeron range, which divides Boeotia from Attica, and on the southern edge of the Boeotian plain. It played an important role in Greek myth, as the site of the stories of Cadmus, Oedipus, Dionysus and others...

, he repulsed the Epirotes and later invaded Greek territory as far as Thessalonica, where they were convinced to turn back by the empress Eirene of Montferrat

Eirene of Montferrat

Yolande of Montferrat was the second Empress-Consort of Andronikos II Palaiologos, the ruler of Constantinople and the entire Byzantine Empire, and heiress of the Margraviate of Montferrat.Born in Casale, she was daughter of William VII, Marquess of Montferrat and his second wife Beatrice of...

.

In 1307, Guy was made bailiff of Achaea

Achaea

Achaea is one of the regional units of Greece. It is part of the region of West Greece. It is situated in the northwestern part of the Peloponnese peninsula. The capital is Patras. The population exceeds 300,000 since 2001.-Geography:...

 by its new prince, Philip I of Taranto

Philip I of Taranto

Philip I of Taranto : of the Angevin house, was titular Emperor of Constantinople , despot of Epirus, King of Albania, Prince of Achaea and Taranto, and Lord of Durazzo....

. He governed well, but for barely a year. He died young, but respected and renowned for his chivalry

Chivalry

Chivalry is a term related to the medieval institution of knighthood which has an aristocratic military origin of individual training and service to others. Chivalry was also the term used to refer to a group of mounted men-at-arms as well as to martial valour...

 and manners, typical of the Frankish courts kept in Greece. He was buried in Daphne

Daphne

Daphne was a female minor nature deity. Pursued by Apollo, she fled and was chased. Daphne begged the gods for help, who then transformed her into Laurel.-Overview:...

 alongside his ancestors. He left no heirs and the De la Roche line of dukes came to an end; Athens was disputed among rival claimants until the parliament of the duchy elected Walter V of Brienne

Walter V of Brienne

Gautier or Walter V of Brienne was born in Brienne-le-Château, Aube, Champagne, France. He was the son of Hugh de Candie des Brienne, known as Hugh of Brienne, Count of Brienne and Lecce, and Isabella de la Roche, daughter of Guy I of la Roche, Duke of Athens...

.