Yes, I consulted a thesaurus, no help (or I couldn't use it properly). I need an adjective that describes a process that develops rapidly and is full of events (regardless of whether they are good or bad) as opposed to something stagnant, not changing. For example, '[word] political life of [a country]'. 'Turbulent' has negative connotations, I need something neutral or, maybe, slightly sarcastic. I also know the word 'eventful'. It doesn't fit either, in my view.
You could use the word "unstable", which doesn't necessarily suggest that it changes quickly, but it does mean something could change at any time.
Otherwise, I can't think of a single, widely-used adjective to describe something that changes rapidly. Those are two different qualities. You might as well ask for a single adjective that describes something that moves and is red.
I would suggest you use a hyphenated compound of two words instead. Here are some possibilities:
Any of the above could potentially be mixed-and-matched, although these sound the most idiomatic to my ears.
There is also the expression "in a state of flux" which pretty much means unstable, but it wouldn't insert into your sentence without some re-writing.