Philip I of Hesse was born as the eldest son of William II, Landgrave of Hesse and William the Second's wife, Anna of Mecklenburg-Schwerin. The early years of Philip I were marked by a considerable unrest. The father of Philip I, William II, had died when Philip I was only four years old. The reason for the death of Philip the First's father was syphilis.
The death of Philip's father led to a series of events which plunged Philip I of Hesse into the political controversy over its Regency. The noblemen of Hesse took temporary reigns and had separated Philip I from his mother, Anna of Mecklenburg-Schwerin. His mother had to struggle with the noblemen of Hesse over the reign over Hesse. In 1514, Philip's mom had succeeded in her fights over the reign and became the regent on Philip the First's behalf. Philip I and his mother, Anna of Mecklenburg-Schwerin, had reunited in 1514 after a period of separation.
Although Philip's mom won over the noblemen of Hesse, the struggles over authority had continued. An end has come to all the struggles over authority to Philip I and his mother after Philip I had been proclaimed as the Landgrave of Hesse in 1518. His actual assumption of power began in the year of 1519.
In the month of March of 1518, the Emperor Maximilian I proclaimed Philip I to be of age. Although he retained the Hesse province in his name, there were a lot of counselors around him advising him how to rule the Hesse province.
The event that changed the life of Philip I of Hesse was his initial meeting with Martin Luther. Philip's initial meeting with Martin Luther was in 1521 when Philip I was only 17 years old, and before he got the Landgrave title. Philip met with Martin Luther at the Diet of Worms in Worms, Germany. Little did Philip I know how would his meeting with Martin Luther impact his life.