halo 4 humanity vs. forerunners

I have just read that “apparently” in Halo 4, you learn that humans were at war with the Forerunners and lost. The Forerunners then put humanity back to the stone age by using a process called devolution. If this is so, then why do the covenant need a humans to activate the rings in Halo 3. It has seemed that humans were related to the Forerunners throughout the Halo videogames. The war seems alittle “far-fetched.” I understand 343 industries wants to add new twists to the Halo Frachise and increase interests with new details, but it raises a lot of questions. Sorry if I seem like a nag for pointing this out, but it bothers me and seems contadictory to the other Halo games.

Read cryptum and then primordium trust me they will answer alot for you :]

Guy above me said it.

The Human-Forerunner War is covered in Halo: Cryptum.

Over 100,000 years before Halo: C.E., Humanity was an advanced space-faring race. They settled many worlds, including many with Precursor ruins, tapping into their technology. The war began when humans started to encroach on Forerunner space, caused by the threat of the Flood. Humanity fought a two-front war, against the Flood and against the Forerunners. The Forerunners didn’t know about this until after they beat the Humans back and defeated them at Charum Hakor, a major Precursor planet.