King's Bounty was predecessor for all Might & Magic Heroes games, regarding that it was a bit different. Player was visiting individual locations and fulfilling quests here with his army. The game was created by Jon Van Caneghem in 1990.
After the license for M&M was sold to Ubisoft, King's Bounty wasn't part of the deal and it was bought by 1C Company in 2007. Based on that 1C Company published following sequels:
2008 - King's Bounty: The Legend (About Royal Treasure Searcher Bill Gilbert)
2009 - King's Bounty: The Armored Princess (About Princess Amelie)
2010 - King's Bounty: Crosswords (Brought Map Editor and some short campaigns)
2011 - King's Bounty: Legions (Online and mobile iteration, one and only developed by Nival)
2012 - King's Bounty: Warriors of the North (Nordic Inspiration)
2014 - King's Bounty: The Dark Side (To see the world from the other perspective, play for Vampire, Orc Warrior or Succubi. Although it's still developed by 1C-SoftClub / Katauri Interactive, there was a different team behind it. )
Apart from one they were developed by Katauri Interactive.