I have :
Astonishing platemail of Strombran - Strombran I believe was a realm in Atamara; a sunken islnd now.
Correct.
Putrid pendant of Lanard's brains - I guess Lanard is/was a character in game.
Yes, but in this case, this was a GM manually-created unique item on Beluaterra for the invasion. Lanard being some human slain by daimons in battle or execution and his remains desecrated by daimons to form a grotesque unique item. There's quite a few of these on the island.
Cookbook of the Barony of Icegate - If I recall, Icegate was the Capital of the realm of Barony of Makar; Also in Atamara.
Again, correct.
Smoking sceptre of Ankar - I guess Ankar is/was a realm or region. Maybe a character name even.
Another GM manually-created unique item related to the Beluaterra Invasion. Ankar is the unspoken name of Akkan, too sacred to be vocalized.