The Fate of the Latin EmpireIn many ways, though, the most revealing point about the Brienne
brothers is that they never returned to the Latin empire to try to claim
the great lordships that had once been promised to them in the treaty of
Perugia. However, they did have a great deal to do with their sister, the
Empress Mary. Hence, we will turn to examine her early career, with
particular emphasis on points of contact with her kinsmen.
At the age of around ten, Mary had been left behind in Constantinople
when her new husband, Baldwin, and her even younger brothers had set
sail for the West in 1236. Mary’s father, the Latin emperor John, died in
March 1237, and her mother, Berengaria, seems to have followed soon
afterwards. These events catapulted little Mary into prominence, as the
sole surviving member of the Latin imperial family who was still present
in the city. However, she was still too young to play anything other than a
formal or decorative role, and this situation persisted until her husband
returned to Constantinople in 1239–40.^43
Baldwin’s long sojourn in the West had been nowhere near as success-
ful as he had hoped. The most famous event of the period was, of course,
the purchase of Constantinople’s most precious relic, the Holy Crown of
Thorns, by Louis IX, who constructed the celebrated Sainte-Chapelle to
receive it.^44 Another way for Baldwin to get his hands on more resources
was, of course, to lay claim to his own Western inheritance: above all, the
marquisate (or county) of Namur and the lordship of Courtenay. In the
end, there were difficulties over both of these. Baldwin’s sister, Margaret,
was in possession of Namur, and he had to press his claims by force.
Baldwin then assigned parts of it as a dower to his wife before mortgaging
the lordship to King Louis for the sum of 50,000l. parisis.^45 Courtenay,
by contrast, caused far less trouble at first. Later, however, when
Baldwin was back in the East, he tried to cash in once again, granting
the lordship to Geoffrey II, prince of Achaia, who was in a position to
help Constantinople. King Louis, though, would have none of this. In
his eyes, Courtenay was an ancestral lordship that belonged to Baldwin
(^43) For Baldwin’s return, see N. Chrissis,Crusading in Frankish Greece: A Study of Byzantine-
Western Relations and Attitudes, 1204– 1282 (Turnhout, 2012), 120–6.
(^44) See‘Régestes des empereurs latins de Constantinople’, compiled by B. Hendrickx, in
Byzantina14 (1988), nos. 191–7; and also M. Angold,The Fourth Crusade: Event and
Context(London, 2003), 237–40. See also J. M. Martin, E. Cuozzo and B. Martin-
Hisard,‘Un acte de Baudouin II en faveur de l’abbaye cistercienne de Saint-Mariede
45 Percheio(octobre 1241)’,Revue des études byzantines57 (1999), 211–23.
‘Régestes des empereurs latins de Constantinople’, nos. 203, 207; and also Longnon,
L’empire latin de Constantinople et la principauté de Morée, 179.
84 In the Pages of Joinville (c. 1237–1267)