Personal Names

In Ettrea, the format of a person's name depends on their social rank. Usually only people of noble or equestrian rank have a proper family surname.
People of Imperial rank (that is, members of the Imperial Family ) will have a family surname, but convention means that it is not used. Only their title and first name is used. For example "Emperor Otto", "Archduke Tavin".
People of Noble rank also have family surnames, and again convention means that they are not used. For example, Margon Estadmier is the Landgrave / Landgravine of Frauern. He would be known as Margon, Landgrave of Frauern. He would not be known as Landgrave Margon or even Landgrave Margon of Frauern, only ever Margon, Landgrave of Frauern. However, some noble titles in some parts of Ettrea would be said in that order - for example, Prince Casrian of Dimrillien , rather than Casrian, Prince of Dimrillien. There are no easy principles to know the format for noble titles and names, and it can be a breach of etiquette to get it wrong.
Knights and dames  have family surnames and use them, along with their title, for example Sir Henrik Ost, Dame Helfinn Urgenreitz. The wife of a knight takes his surname, unless she is of noble rank, in which case she keeps her own noble surname, but does use it. For example, Sir Henrik Ost has married twice. His first wife was a burgheress , Esminn of Krunebrug. When they married, Esminn took Sir Henrik's surname and became Lady Esminn Ost. After Lady Esminn died, Sir Henrik married again, this time to Mistress Saraa of Starstad, youngest daughter of Baron Karbitt of Starstad, whose surname was Starcomb. Mistress Saraa became Lady Saraa Starcomb. Sir Henrik's non-adult children Junghers and Junghennin  by his first marriage, Tomas and Hemblyn are known as Jung Tomas and Junghenn Hemblyn. However, his infant son by his second marriage, Karlbinn, is known as Master Karlbinn because his mother is of noble rank.
High Elves who can trace their families back to the Old Empire (which is most of them) will also have family surnames and will use them, regardless of their social standing, e.g. Vilelm Dupasser. In Eldrin, the prefix den is frequently used to indicate an elf (almost always a high elf) who can not only trace his or her descent from a family of the Old Empire, but a noble family of the Old Empire. So for example, Laedislau den Habrett  can trace his descent from the noble Habrett family of the Old Empire.
People of Burgher / Burgheress , Forester and Freeman rank can choose names that reference where they are from (e.g. Jaylin of Hennsbrug), their profession (e.g. Karol Juelsmithe), a characteristic they are known for (e.g. Marten Strongbow) or a parent (or more distant ancestor) (e.g. Sherrin Hagardsdohtor or Arsin Moysson).
Peasants and Vagabonds have only a single name, although they often combine it with a nickname (e.g. Tall Bastin, Ugly Tob).