Chlothar I, also referred to as Clotaire I, called the Old (le Vieux), King of the Franks, was one of the four sons of Clovis I of the Merovingian dynasty.
Although his father, Childeric I, had united Francia for the first time, Clovis I divided the kingdom between his four sons. In the year 511 at the age of about 14, Clothar I inherited two large territories on the Western coast of Francia, separated by the lands of his brother Charibert I's kingdom of Paris. Chlothar spent most of his life in an unedifying struggle to expand his territories at the expense of his relatives and neighbouring realms in all directions.
His brothers avoided outright war by cooperating with his attacks on neighbouring lands in concert or by swooping on lands when the ruler died. The spoils were shared between the participating brothers. By the end of his life, Chlothar had managed to reunite the Francia by outliving his brothers and grabbing their territories after they had died. But upon his own death, the Frankish kingdom was once again divided between his own four surviving sons; a fifth son had rebelled and was killed, along with his family.
Chlothar's father, Clovis I, had converted to Nicene Christianity, but Chlothar, like other Merovingians, did not consider the monogamy taught by Christianity should be expected of royalty; he had five wives, more from political expediency than for personal motives. Although at the instigation of his queens he gave money for several new church buildings, he was a less than enthusiastic Christian and succeeded in introducing taxes on church property.
King Chlothar I ruled:
In other words, Chlothar I eventually (558-561) inherited all of the Frankish kingdoms (domains) after the deaths of his brothers or their successors. After his own death though, the kingdom was once again split among his four sons.