The Aegean scope of Byzantine activity gives little indication of where
the city’s naval strength really lay. In order to understand this, we must
get behind the story of Philip’s capture of the convoy of ships through the
Bosporus. The combined evidence of the different Greek historical and
forensic sources on this incident, which are given particular coherence by
a relevant passage in theCommentary on Demosthenesof Didymus,
make it clear that ships were regularly convoyed through the channel
and the Hellespontine Straits, in order to avoid the kind of arbitrary
seizure along this route that Philip’s capture in 340bcrepresented.
Gabrielsen has argued that thesitopompeia,the convoying of grain and
other commercial transports, had become a more or less regular way in
which ships crossing the Straits and Bosporus to the Black Sea arrived at
Byzantion, particularly if they had to wait for favourable winds before
proceeding northwards from there.^120 Similarly, convoys gathered at
Hieron on the return leg of the journey, to be escorted back into the
Hellespont.^121 The duty of escort was undertaken by Athenian ships in
thefifth and fourth centuries. Thereafter, Byzantion probably took over
the same kinds of functions. The cost of such protection came to be built
into the budget of bottomry loans (Dem. 35. 10–13). The forensic
speeches of Demosthenes contain frequent references to the hindering
of merchant vessels (ta ploia kōluein) and the actual commandeering of
merchant ships to unplanned harbours.^122 The passage from the Helle-
spontine Straits to the Bosporus became a bottleneck for ships, which
were obliged to follow the winds and currents peculiar to these shores. In
Chapter 43 of Book 4 in hisHistories,Polybius describes how the cur-
rentsflow in a zigzag manner from the Bosporus in the direction of
Byzantion, making it easy for ships to stop off at the latter and difficult to
dock at Chalkedon. The historian’s account at this point of his narrative
is entirely focused on the behaviour of waves, currents, ships, and natural
features of the shoreline. He refers to the sanctuary of Zeus (Ourios) at
Hieron and to the Hermaion on the European side, north of Byzantion.
These more contextual details are woven into a reflection on the gradual
silting up of the shorelines adjacent to the Black Sea and Maiotic Sea (the
Sea of Azov), which diverts from the principal subject in this part of
Book 4, namely the extraordinary success of Byzantion and its highly
(Dumitru 2006, 147 with further refs). The role of the Byzantine ships is otherwise
unknown, although a number of Byzantine sailors, perhaps including an admiral, were
voted honours at Athens; Dittenberger and others have dated these in connection with the
events at Chios: Dittenberger,SIG^2 II, 580 =IGII^2 884 (ibid. 150).(^120) Gabrielsen 2007, 299–311. (^121) Moreno 2008, 646–70.
(^122) Dem. 17.19–21 (337bc); Gabrielsen 2007, 311–13, with discussion.
Regionalism and regional economies 241