Theobald I of England (13 May 1179 – 24 May 1201) was King of England, Duke of Normandy and Count of Champagne from 1197, when his elder brother died in Jerusalem, and 1201, when he died.
From the age of eight, Theobald was the commander of the English forces in Wales, who had conquered much of that region under his father. The Welsh excelled in low-grade guerrilla warfare and weren't entirely crushed until 1193. This victory was not well-received by the barons and earls who had assisted in the war as they had expected Palatinates and special privileges in return for quashing any further unrest and this did not seem likely. Thus, in 1195, Richard de Clare, Earl of Hertford rebelled with several friends and relations, marching on Winchester. The young Theobald, who was acting as a sort of unofficial regent, met them unarmed and unescorted and proposed an invasion of Ireland to be undertaken by former Marcher barons without royal assistance. This was agreed to and the Norman Conquest of Ireland began in earnest in 1196.
Due to this promising start, when news came to Europe that Henry III had died from falling off a balcony Theobald was tacitly allowed to rule as King before his majority (he was not quite eighteen). The only major acts done in his reign were the Statute of Jewry, which allowed Jews to live and work without fear of official prejudice (though private racism still continued) and the Statute of Succession, which stated that if the king had no sons, his closest adult male relative would succeed. In 1198, however, Jerusalem was lost again to the interloping Christians and Pope Innocent III called the Fourth Crusade. Due to the mixed performance of his family in Levantine affairs (his great-grandfather had run away just as it started to get difficult) Theobald was keen to set the record straight as regards the House Blois and its reputation for cowardice. He quickly emerged as a main leader, mainly because everyone else who had sufficient status was sick of the whole concept. In 1199, when he was still getting ready to set off, he married Blanche of Navarre and two years later he finished packing and set off for the Holy Land. Unfortunately for him he immediately died of a heart attack brought on by abject fear and dies on May 24, 1201.
His widow was very pregnant at this time and gave birth to Theobald II on the 30th. Thus, Theobald II is one of the few monarchs to be a king before he was even born. A succession of regents ruled for him until he came, during which time his female cousins continually pestered anyone who would listen for their rightful inheritance.