These two daggers are either from Sudan or, Eritrea. I have often seen them being worn by herdboys when guarding the animals. I'm sure Will has seen plenty on his travels in that Country.
Usually they are worn on the left arm and are not used as we might expect. The hand is put through the loop and it is pulled to the outside of the upper arm. The handle is worn pointing downwards towards the wrist. Should they need to pull it quickly, the right hand just reaches across to the grip and pulls downwards. Quite deadly.
Both of these are of a good quality - with better metal then usually seen. The hide will be camel and it is nicely tooled for the decoration. Top and bottom on both, is python skin - which has many secret meanings to African tribes.
One has a plain wooden handle, with simple blade decoration - the other, is bone, ivory or, more likely Hippo tusk. Inlaid and with a good decoration on the blade.