were left to themselves, and the process of differentiation between Serb
and Bulgar in Macedonia, by which in time the Macedonian Slavs would have
become either Serbs or Bulgars, ceased. The further development of the
Macedonian question is treated elsewhere (cf. chap. 13).

The Serbs, who had no permanent or well-defined frontier in the east,
where their neighbours were the Bulgars, or in the south, where they were
the Greeks and Albanians, were protected on the north by the river Save
and on the west by the Adriatic. They were split up into a number of
tribes, each of which was headed by a chief called in Serbian _[)z]upan_
and in Greek _arch[=o]n_. Whenever any one of these managed, either by
skill or by good fortune, to extend his power over a few of the
neighbouring districts he was termed _veliki_ (=great) _[)z]upan_. From
the beginning of their history, which is roughly put at A.D. 650, until
A.D. 1196, the Serbs were under foreign domination. Their suzerains were
nominally always the Greek emperors, who had 'granted' them the land they
had taken, and whenever the emperor happened to be energetic and powerful,
as were Basil I (the Macedonian, 867-86), John Tzimisces (969-76), Basil
II (976-1025), and Manuel Comnenus (1143-80), the Greek supremacy was very
real. At those times again when Bulgaria was very powerful, under Simeon
(893-927), Samuel (977-1014), and John Asen II (1218-41), many of the more
easterly and southerly Serbs came under Bulgarian rule, though it is
instructive to notice that the Serbs themselves do not recognize the West
Bulgarian or Macedonian kingdom of Samuel to have been a Bulgarian state.
The Bulgars, however, at no time brought all the Serb lands under their
sway.

Intermittently, whenever the power of Byzantium or of Bulgaria waned, some
Serb princeling would try to form a political state on a more ambitious
scale, but the fabric always collapsed at his death, and the Serbs