So its known that there was no such thing as a 'viking state,'

What do you mean by that, exactly? Norway, Denmark and Sweden were all Kingdoms; Iceland in fact was supposedly settled by refugee Jarls and other dispossessed noblemen and retinue from Harald Fair-Hair's unification of Norway in the 9th century, which remained an independent "republic" until [1362 when it entered into personal union with the King of Norway](http://en.wikipedia.org/wiki/Old_Covenant_(Iceland)). Mind you, early Norse monarchs did not enjoy absolute authority and had to deal with their subject jarls' (chieftains) many and powerful rights. But as far as I can gather, this was fairly common in the early/mid medieval world, where kings were often first among equals rather than the absolute rulers Europe would see emerge after the middle ages (see King Louis XIV of France for an example of such an "absolute monarch").

how is it, then, that they have similar religions? if they all fight and all were different, how does one define 'norse paganism?"

I hope someone with real expertise and ability to properly source can weigh in on this, but...

First of all, the core "Norse Gods" are ancient. Wodanaz (Odin) was known to the Romans. Second, the oldest sources we have about Viking religion are from after the conversion to Christianity; Gesta Hammaburgensis is from 1080, Konungsbók/Codex Regius is from 1220, and Snorra-Edda is also early 13th Century. Note that in the case of the two Icelandic sources I mention (Codex and Edda), they are written more than two centuries after the country's conversion to Christianity in ~1000AD, the last of the Norse countries to do so.

With that in mind, it's unlikely that Norse Paganism was very unified across the Norse world. Viking culture was highly oral with very limited written sources save for perhaps Scandinavian runestones.

I wish I could do better, but maybe someone more able can expand/correct me.

Please note that I am not linking to Wikipedia as a source, but as a way for you to research things if you are in doubt of what they mean. A lot of the things I am talking about here are adequately sourced on those pages however, if you want me to get some actual sources on something I will.

So its known that there was no such thing as a 'viking state,' as in a single nation with vikings. instead it was a group of chief led tribes that didnt really get along well, am i right?

No. A Norse kingdom would be Denmark which we know had a king, Godfred, as far back to the time of Charlemagne when, according to legend, he invaded Frisia and had Danevirke built.

Some of the most famous "Vikings" would even be kings such as Sweyn Forkbeard and Cnut the Great who ruled Denmark, Norway and England. Also for reference, the Danelaw was created a few decades earlier to this.

But you are partly right for a group of chiefs did lead for a time in some places in Scandinavia. Although it might be more prudent to consider them elected officials as they were voted into power through tings, a kind of village council. Our parliament in Denmark today is actually called Folketinget which roughly translates to Assembly of the People.

if they all fight and all were different, how does one define 'norse paganism?'

Usually it is simply defined as the Germanic pantheon that lingered in Northern Europe after Charlemagne's Saxon wars. It is often attributed to just the Norse, but that is simply wrong to do. It was not unified faith and that was its weakness compared to the organized religion of Christianity.

Today we know some things through the Edda, but since a lot of the tales were sung by skalds a lot have been lost. Sadly it seems, as magnificent as they are, then runestones are not the best way to retain knowledge.

Your idea that there was not a single Viking state is correct, and even though some people tried (like Harald Bluetooth claiming rights in modern Norway as well as Denmark), Scandinavia was never united. However, I am confused why you thing a unified state is necessary for a uniform religion. Indonesia and Morocco never were part of the same state, yet shared a religion.

The other posters are wrong in pointing you to the existence of Viking states, by the way; the earliest definite state we know of is Harald Bluetooths conquest of modern Denmark, and he was a Christian. There were no pagan states, earlier people like Godfred and Harald Fairhair are legendary and not to be trusted as historical truth.

That said, there was no unified Norse religion, and I'm pretty sure there was no 'religion' in the strict sense of the word at all; instead, you have a mosaic of regional and individual beliefs, although they shared some common traits (basic ideas about the structure of the world, or common gods like Frey and Thor, for example). This was partly because even though people belonged to different political groups, they still travelled a lot and were in contact with eachother. We know that Uppsala, for example, was significant also for Danish people as a religious center, and possibly there were more of these very special imporant places throughout the Baltic world. People also traded with eachother, or married into eachothers families, and ideas and beliefs could be spread or exchanged in this way as well; a conquest-scenario, like how Islam spread through the Mediterranean in the same period, is not required.