thane/THān/
Noun:

• (in Anglo-Saxon England) A man who held land granted by the king or by a military nobleman, ranking between an ordinary freeman and a...
  
• (in Scotland) A man, often the chief of a clan, who held land from a Scottish king and ranked with an earl's son.

thane (commonly), thegn
1. (in Anglo-Saxon England) a member of an aristocratic class, ranking below an ealdorman, whose status was hereditary and who held land from the king or from another nobleman in return for certain services
2. (in medieval Scotland)
a. a person of rank, often the chief of a clan, holding land from the king
b. a lesser noble who was a Crown official holding authority over an area of land
Becoming Thane in Skyrim is fairly easy in my opinion.. One thing sticks in my craw though..
being the Thane of a hold allows you to avoid being arrested for a crime under 3000 gold in that hold by reminding the guards of your status when they arrive, but only once.

In some of the large holds, you will also receive a http://www.uesp.net/wiki/Skyrim:Followers#Housecarls.

In http://en.wikipedia.org/wiki/Viking_Age, housecarls (http://en.wikipedia.org/wiki/Old_Norse_language: húskarlar, singular húskarl; also anglicised as huscarl (http://en.wikipedia.org/wiki/Old_English form) and sometimes spelled huscarle or houscarl) were either non-http://en.wikipedia.org/wiki/Slavery_in_medieval_Europe manservants, or household troops in personal service of someone, equivalent to a http://en.wikipedia.org/wiki/Bodyguard to http://en.wikipedia.org/wiki/Scandinavia lords and kings. This institution also existed in http://en.wikipedia.org/wiki/Anglo-Saxon_England after its http://en.wikipedia.org/wiki/Anglo-Saxon_England#England_under_the_Danes_and_the_Norman_conquest_.28978.E2.80.931066.29 in the 11th century. In England, the royal housecarls had a number of roles, both military and administrative; they are well-known for having fought under http://en.wikipedia.org/wiki/Harold_Godwinson at the http://en.wikipedia.org/wiki/Battle_of_Hastings. The original http://en.wikipedia.org/wiki/Old_Norse_language term, húskarl, literally means "house man"; see also the http://en.wikipedia.org/wiki/Old_English_language term http://en.wikipedia.org/wiki/Churl or ceorl, whose root is the same as the http://en.wikipedia.org/wiki/Old_Norse karl, and which also means "a man, a non-servile peasant".^{http://en.wikipedia.org/wiki/Housecarl#cite_note-0}