Palmer J, Slater G. Ainderby Steeple Open Domesday. http://opendomesday.org/place/SE3392/ainderby-steeple/  Accessed April 10, 2018.

Ansketil derives from Old Norse, directly introduced to England. The name is often found as
Asketil, Aschetil, Anschetil and similar (in Latin, as Aschetillus, Ansketillus, etc.). Derived from Old Norse áss “god” and ketill “cauldron, helmet”, so God’s helmet. See detailed etymology here.

Ansketil de Fourneaux is also listed in the Domesday book, and held more land than Odo de Fourneaux. While Odo held land, around Devon and Cornwall, Ansketil held lands to the north and north east of London. He had so much land he had to provide knights for the local minor nobility. 

List of holdings held by Ansketil in the Domesday Book:

Village	Shire	Holder in 1066	Fiscal Value	Link to Original Domesday Text
Barham	Cambridgeshire	Eadgifu [Edeva] the fair	2.88	Ansketil + Barham
Swannington	Norfolk	Thorbern ‘of Swannington’	0.5	Ansketil + Swannington
Swannington	Norfolk	Thorbern ‘of Swannington’	0	Ansketil + Swannington 2
Harling	Norfolk	Ulfkil ‘of Harling’	4.0	Ansketil + Harling
Ainderby Steeple	Yorkshire	Thorkil ‘of East Appleton’	6.0	Ansketil + Ainderby Steeple
Ainderby Steeple	Yorkshire	Ulfkil ‘of Crakehall’	3.0	Ansketil + Aindeby Steeple 2

You can view a Map of these Holdings here.

According to Keats-Rohan, Alan also owed a ‘fee of the honour of Richmond’ in other words had to provide the service of 8 nights, who rendered castle guard in October to November.  Castle guard was a feudal arrangement where a higher noble placed a kind of a tax, whereby knights were provided in return for the provision of land. The number of knights (knight’s fee) was based on the fief (amount of land held) so fee and fief are intertwined in meaning. 

A wonderful 15th Century Manuscript records the the investiture of Alan as Earl of Richmond by William the Conqueror, seated in the manuscript below, Alan (kneeling at the feet of the King) being granted the Honour of Richmond  (holding Richmond Castle on behalf of the King).  

William gave Richmond Castle to Alan in thanks for his support during the conquest.  Richmond Castle is one of the best preserved castles dating back to the 11th century. 

Variations on the name

For those curious, variants of Ansketil in the Domesday Book include: Anschetel, Anschetellus, Anschetil, Anschetilius, Anschetillus, Anschil, Anschitil, Anschitilius, Anschitillus, Anschitilus, Anschittillus, Anscitillus, Ansketillus.

Please see a photo of the keep of Richmond Castle.