Borg wanted moneys.
Before the war, NPO was IIRC, 3rd in fleet, 2nd in econ. Borg was 2nd in fleet, 3rd in econ. LUE and Ragex, I don't recall their stats. But they were about equal.
Thus, Borg+Ragex declared war on LUE in like May. (and other minor allies, most either destroyed or hollow shells) Only Borg was fighting NPO though. I don't know their forum stated reasons, but it was pretty much for money. We had money, they had fleet, so they go and use it to take our money. And drop us 2 or 3 ranks.
The Borg kind of took NPO off guard, and quickly destroyed a lot of our fleet, scared off lots of newbies, dropped a lot of our econ. The first month was actual large scale fighting. Then by that time, bases became well defended enough to not be taken without horrendous losses. Generally. So it became a cold war. We kill each other's occupations, kill each other's fleet if we see it out in the open, hit a weak base, and don't do much otherwise. Then NPO declared on Ragex, and Ragex started getting destroyed a bit with pent up NPO fleets combined with LUE's fleets. And then more stalemate.
The war dragged on for the entire summer, only ending 2 weeks before September with a peace with NPO. Then about a week later, LUE establishes peace.
The end result is that NPO and LUE had to pay a 2 week occupation with no pillages. Immediate release of Borg and Ragex bases.