Two things first:
One, punctuation please; for the love of all things break your sentences up so its not one gigantic run on block of text.
Two, use of a spell checker often goes a long way; most internet programs have one built in these days, and if you have access to something like microsoft word then that has it as well.
as dorn's righteous travelled through space with there small battle fleet
What exactly constitutes as a small fleet in your mind anyway? What kinds of ships were present and how many?
after there numbers where drasticly depleted when facing a small band of eldar pirates who had some how managed to retrieve a eldar revenat titan......
For this I suggest doing a fair amount of research and working with someone who knows a fair amount about the Eldar. You will be extremely hard pressed to find a craftworld willing to allow corsair Eldar to retrieve one of their titans if it can be salvaged.
Also, as far as retrieval is concerned, this would be done through a massive webway gate as titans are rather large constructs.
after dorns righteous dified orders and stayed on the world of .......... (havent thought of name)
Who was giving them these orders, what were these orders they refused, and by what right did this person/group have to be ordering around a chapter of space marines?
This is once again something to be doing some research on; space marine chapters govern themselves, they answer to themselves and rarely any other. Other Imperial organizations can request or demand things of them (or make accusations) but within a chapter the ultimate authority in regards to giving orders to its parts lies with the chapter master and no other.
to protect its people agaisnt the eldar threat they were excommuncated but did not give up to execution and ran
Once again, by what reason or right does this group/person have to keep part of a space marine chapter from protecting humanity from its enemies? Was there something about the planet that they wanted to keep the marines from? Was it a tainted or cordoned planet and exposure would corrupt/damn?
one day when in space 4 imperial emporer class battleships
Another point to do some research, a battleship is a powerful vessel in its own right, a single one commanding an entire fleet. You will rarely, if ever, find a single Imperial battleship flying about, let alone four being committed to seeking out and destroying a marine fleet.
That being said, did these four battleships have any support vessels? Fleets of their own?
emerged and made quick work of the small space marine fleet little did they know that the ships had been completly deserted
Why were the vessels deserted? Was there something wrong with them? Did they have some alternate means of travel? It is not a very smart move to allow your mode of travel in the galaxy to be destroyed without having something else.
and had dropped of to the nearest forge world were they asked the adeptus mechanius for a small fleet but know one knows about the awnser that was given.....
If the chapter is excommunicated, why would a forgeworld, run by the mechanicus, even be willing to help them? They are, after all, branded traitors of the Imperium regardless of their actions.
When making a chapter, before working on the background and history of your chapter it is a good idea to have some other things decided and filled in first. Things like the following:
Name
Founder
Primarch
Founding
Colour
Battle-cry
Combat doctrine
Current strength
Homeworld (if applicable)
Galactic location
These things, they help to give your chapter some structure before working on its history.
