AboutChibitalia and Holy Roman Empire were briefly raised together as infants, before Grandpa Rome took Chibitalia away to live with him for an indeterminate period of time. By the time Chibitalia returned to his place of birth, the other children had become bullies to him and Holy Roman Empire vowed to make Chibitalia part of his "New Roman Empire".
Chibitalia eventually wound up claimed by Austria, on the behalf of Holy Roman Empire, after a period of war. The two children lived together in the household, HRE harboring a crush on Chibitalia, who he believed to be a girl (due to his feminine sense of attire).
However, life soon became uneasy in the household. HRE soon gave Chibitalia the offer of becoming part of his "New Roman Empire", which the other child refused, remembering what had eventually happened to his grandfather. HRE left the household, leaving only Austria, Hungary, and Chibitalia behind.
It is at this point in time which the published version of the manga ends, with Chibitalia crying as HRE departs. ~(from Hetalia Archives - Axis Powers Hetalia)