Svatopluk the Lion was the duke of Bohemia from 1107 to his assassination. He was a son of Otto I of Olomouc

Otto I of Olomouc

Otto I of Olomouc was Duke of Olomouc in Moravia from 1061 to his death in 1087.He was the youngest son of Bretislaus I, Duke of Bohemia and Judith of Schweinfurt...

 and Euphemia of Hungary and grandson of Bretislaus I of Bohemia

Bretislaus I of Bohemia

Bretislaus I , known as Bohemian Achilles, of the house of the Přemyslids, was the duke of Bohemia from 1035 till death.-Youth:...

.

Duke of Olomouc

Olomouc

Olomouc is a city in Moravia, in the east of the Czech Republic. The city is located on the Morava river and is the ecclesiastical metropolis and historical capital city of Moravia. Nowadays, it is an administrative centre of the Olomouc Region and sixth largest city in the Czech Republic...

 since 1091, he was at enmity with his cousin Bořivoj II

Borivoj II of Bohemia

Borivoj II was the duke of Bohemia from 25 December 1100 until May 1107 and from December 1117 until 16 August 1120. He was the younger half-brother and successor of Bretislaus II....

, whom he sought to drive out, thus precipitating a new civil war

Civil war

A civil war is a war between organized groups within the same nation state or republic, or, less commonly, between two countries created from a formerly-united nation state....

. The Emperor Henry V could not ignore the anarchy in Bohemia. He summoned Svatopluk, who dared not resist, and retained him captive and made him restore Bořivoj. Soon, he became reconciled to Svatopluk and released him. Svatopluk made him godfather of his new son, who was baptised Wenceslaus Henry.

Nevertheless, Svatopluk returned to Bohemia to expel Bořivoj. In 1108, the emperor had to intervene in Hungary

Hungary

Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...

 on behalf of Prince Álmos

Prince Álmos

Álmos was a Hungarian prince, the son of King Géza I of Hungary, brother of King Kálmán. He held several governmental posts in the Kingdom of Hungary....

 against his brother King Coloman. Svatopluk joined the expedition, but had to return to Bohemia, where Borivoj had made and attack with the support of Bolesław III Wrymouth, an ally of Coloman. Henry failed to seize Pressburg and Coloman was free to devastate Moravia

Moravia

Moravia is a historical region in Central Europe in the east of the Czech Republic, and one of the former Czech lands, together with Bohemia and Silesia. It takes its name from the Morava River which rises in the northwest of the region...

 (then part of the Duchy of Bohemia). Henry desired to avenge the Polish intervention which caused his Hungarian fiasco. He invaded Poland

Poland

Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...

 with the support of Svatopluk. Svatopluk was assassinated on 21 September 1109 in the tent of the emperor at the Siege of Glogow by a member of the family of Vršovice, whose chief, Mutina, he had decapitated for the support he had given to Borivoj. He was succeeded by Bořivoj.