The backstory I devised for my version of the Clone Wars:
Following the Light and Darkness War, the Galactic Republic was at peace. Aided by the Holy Order of the Jedi Knights, the Republic experienced a period of stability and prosperity which endured nearly a thousand years. But gradually, the Republic declined. As the governance of the Galactic Senate faltered under a stagnant bureaucracy, megacorporations rose in power. More-and-more senators, seduced by power and wealth, allied themselves with corporate interests, and the largest megacorporations had their own representatives placed in the Senate. The Jedi, formerly quasi-anarchist warrior monks who’d served the peoples of the Republic irrespective of the state, became a branch of the Republic Armed Forces, answerable to the Senate and its puppet masters.
In the final century of the so-called Great Peace, cloning was perfected by Spaarti Creations, a biotech company based on the planet Jhantor. Engineered for strength, stamina, and servility, clones were mass-produced as a cheap alternative to paid organics and droids, utilized for a variety of purposes: menial labour, private armies, etc. The response was overwhelming and multifarious. Humanitarian objections were raised against the use of what amounted to slave labour; workers objected to their loss of employment; conspiratorial thinkers dreaded the prospect of individuals being replaced with clone duplicates; droid manufacturing companies balked at the competition. The subsequent conflicts became known collectively as the Clone Wars. In 61 BBY, the Senate capitulated to the widespread anti-clone sentiment by enacting regulations against cloning technology, placing it under state ownership, strictly controlling its application. In response, Jhantor and its subsidiary worlds seceded from the Republic, forming the isolationist Axis of Spaarti.