Bowser is consistently portrayed as attempting to take over the Mushroom Kingdom, but in early games he was called King Koopa.
What kingdom was King Koopa already the king of?
Bowser is consistently portrayed as attempting to take over the Mushroom Kingdom, but in early games he was called King Koopa.
What kingdom was King Koopa already the king of?
He was the ruler of the Koopa... his army. "Koopa" translates from Japanese as "Turtle Tribe".
Most Koopas seem to operate in a hierarchy-based grouping system. Bowser is the leader of the Koopa Troop, which has invaded Mushroom Kingdom many times and has control over most of the Koopas in the Mario series. Many of these same Koopas are soldiers in this army and have different tasks in the organization based on the abilities of their particular class.
The original game manual describes him "Bowser, King of the Koopa"
Not to get overly semantic, but Bowser would not have to be a sovereign leader for him to be called king. The second definition of KING is:
a person or thing regarded as the finest or most important in its sphere or group
The MarioWiki (linked above) also mentions that some of the Koopa are not aligned with Bowser and live in the Koopa Village,
However, not all Koopas are allied with Bowser. Some Koopas, such as the Koopa Troopas of Koopa Village, live peacefully inside the borders of the Mushroom Kingdom, while others, such as Koopa the Quick in Super Mario 64, simply hold no allegiance and operate independently
http://legendsoflocalization.com/super-mario-bros/manuals/ has the original game manual for Super Mario Bros.
The story provided in that manual states that King Koopa is king of the Koopa, an army of magical turtles.
Super Mario Bros 3 portrays him as being king of the Dark Land.
Source (from Wikipedia):
When the brothers rescue the seventh king, the letter they receive reveals that Bowser has kidnapped Toadstool and is holding her captive in the castle of his own kingdom, Dark Land. The brothers travel through Dark Land, enter his castle, and defeat Bowser in a battle.
Picture of the letter from both the original SMB3 and the All-Stars remake.