Renier of Trit was the first Frankish

Latin Empire

The Latin Empire or Latin Empire of Constantinople is the name given by historians to the feudal Crusader state founded by the leaders of the Fourth Crusade on lands captured from the Byzantine Empire. It was established after the capture of Constantinople in 1204 and lasted until 1261...

 duke of Philippopolis (modern Plovdiv

Plovdiv

Plovdiv is the second-largest city in Bulgaria after Sofia with a population of 338,153 inhabitants according to Census 2011. Plovdiv's history spans some 6,000 years, with traces of a Neolithic settlement dating to roughly 4000 BC; it is one of the oldest cities in Europe...

, Bulgaria

Bulgaria

Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...

) from 1204 to 1205. He was a knight from Trith-Saint Léger, Hainaut

County of Hainaut

The County of Hainaut was a historical region in the Low Countries with its capital at Mons . In English sources it is often given the archaic spelling Hainault....

, on the Fourth Crusade

Fourth Crusade

The Fourth Crusade was originally intended to conquer Muslim-controlled Jerusalem by means of an invasion through Egypt. Instead, in April 1204, the Crusaders of Western Europe invaded and conquered the Christian city of Constantinople, capital of the Eastern Roman Empire...

.

Renier was granted Philippopolis and the territory as far as the river Maritsa

Maritsa

The Maritsa or Evros , ) is, with a length of 480 km, the longest river that runs solely in the interior of the Balkans. It has its origin in the Rila Mountains in Western Bulgaria, flowing southeast between the Balkan and Rhodope Mountains, past Plovdiv and Parvomay to Edirne, Turkey...

 by the Emperor Baldwin I

Baldwin I of Constantinople

Baldwin I , the first emperor of the Latin Empire of Constantinople, as Baldwin IX Count of Flanders and as Baldwin VI Count of Hainaut, was one of the most prominent leaders of the Fourth Crusade, which resulted in the capture of Constantinople, the conquest of the greater part of the Byzantine...

 following the October 1204 partition of the conquered and yet to be conquered lands of the Byzantine Empire

Byzantine Empire

The Byzantine Empire was the Eastern Roman Empire during the periods of Late Antiquity and the Middle Ages, centred on the capital of Constantinople. Known simply as the Roman Empire or Romania to its inhabitants and neighbours, the Empire was the direct continuation of the Ancient Roman State...

. Renier's land lay within the modern realm of Bulgaria

Second Bulgarian Empire

The Second Bulgarian Empire was a medieval Bulgarian state which existed between 1185 and 1396 . A successor of the First Bulgarian Empire, it reached the peak of its power under Kaloyan and Ivan Asen II before gradually being conquered by the Ottomans in the late 14th-early 15th century...

, in territory claimed by Byzantium and subsequently the Franks.

Renier's first campaigns that fall and winter to take possession of his imperial fief were successful, but the next year Bulgarian tsar

Tsar

Tsar is a title used to designate certain European Slavic monarchs or supreme rulers. As a system of government in the Tsardom of Russia and Russian Empire, it is known as Tsarist autocracy, or Tsarism...

 Kaloyan

Kaloyan of Bulgaria

Kaloyan the Romanslayer , Ivan II , ruled as emperor of Bulgaria 1197-1207. He is the third and youngest brother of Peter IV and Ivan Asen I who managed to restore the Bulgarian Empire...

 swooped down and took Adrianople and threatened Philippopolis. Renier, with only a small force remaining at his command, holed up in the castle of Stenimaka. It was during an effort to relieve Adrianople that the emperor Baldwin was captured. In the summer, the Paulicians of Philippopolis tried to surrender the city to Kaloyan, but Renier sallied from his fortress and razed their quarter of the city, leaving the rest to the brave defence of the united Latin and Greek populations. Nevertheless, the city was taken and the Greek quarter burned. Later that same year, the imperial regent Henry of Flanders

Henry of Flanders

Henry was the second emperor of the Latin Empire of Constantinople. He was a younger son of Baldwin V, Count of Hainaut , and Margaret I of Flanders, sister of Philip of Alsace, count of Flanders....

 marched into Bulgaria and relieved Stenimaka

Asenovgrad

Asenovgrad is a town in central southern Bulgaria, part of Plovdiv Province.-History:Asenovgrad was founded by the Thracians as Stenímachos around 300–400 BC. In 72 BC the city was captured by the troops of the Roman Empire as part of the Roman expansion towards the Black Sea. After a long period...

and Renier.