Before the european revolutions in the 19th century, the notion of a national state didn't really exist.
It was more about who controls what. Doesn't mean the actual population of the controlled areas changed much.
To give an example from my country's history, Romania has been divided into 3 provinces until very recent (historically speaking) times.
The first unification happened in 1600 when Michael the Brave, the king of the southernmost province, managed to take control of all 3 for about a year. He didn't proclaim himself king of Romania, he called himself king of Wallachia, Moldavia, and Transylvania.
100-150 years earlier, Stephen the Great, the king of Moldavia hit Wallachia militarily several times during his reign... not to conquer it and unify but to place a king friendly to him on the throne.
Pretty sure you can find examples like this in any country's history. Germany and Italy for sure, since they've been divided politically into smaller provinces for a thousand years.
It was more about who controls what. Doesn't mean the actual population of the controlled areas changed much.
To give an example from my country's history, Romania has been divided into 3 provinces until very recent (historically speaking) times.
The first unification happened in 1600 when Michael the Brave, the king of the southernmost province, managed to take control of all 3 for about a year. He didn't proclaim himself king of Romania, he called himself king of Wallachia, Moldavia, and Transylvania.
100-150 years earlier, Stephen the Great, the king of Moldavia hit Wallachia militarily several times during his reign... not to conquer it and unify but to place a king friendly to him on the throne.
Pretty sure you can find examples like this in any country's history. Germany and Italy for sure, since they've been divided politically into smaller provinces for a thousand years.