Seleukos I King of the Seleucid Empire from 305 BC to 281 BC.
Seleukos I was one of the Diadochi - 'successors' to Alexander III 'the Great'.

Having previously served as an infantry general under Alexander the Great, he eventually assumed the title of basileus and established the Seleucid Empire over much of the territory in the Near East which Alexander had conquered.

Seleucus founded a number of new cities during his reign, including Antioch (300 BC) and in particular Seleucia on the Tigris (ca. 305 BC), the new capital of the Seleucid Empire, a foundation that eventually depopulated Babylon.
Seleukos I
Epithet: Nikator ("the Victor")
An AR Tetradrachm struck 261-246 BC in Susa
Obverse: head of young Herakles wearing lion's skin right

Reverse: Zeus seated left, leaning on scepter, holding eagle; ΣEΛEYKOY // (TAYP) // (ΔYP) / BAΣIΛEΩΣ

Diameter: -
Die Orientation: -
Weight: -
in the name of Seleukos I
SC 603.3c; HGC 9, 235
An AE unit struck 290-281 BC in Syria
Obverse: Winged head of Medusa right, locks of snake-hair protruding from forehead

Reverse: BASILEWS / SELEYKOY, bull butting right, uncertain control monogram between hind legs

Diameter: -
Die Orientation: -
Weight: -
No notes for this coin
No references provided for this coin
An AE unit struck 296-280 BC in Seleucia on Tigris
Obverse: Horned and bridled head of horse right

Reverse: Anchor, BAΣIΛEΩΣ // ΣEΛEYKOY, monogram

Diameter: -
Die Orientation: -
Weight: -
No notes for this coin
SC 146; ESM 46; SNG Spaer 135.
An AR Tetradrachm struck 311-300 BC in Babylon
Obverse: Head of Herakles right, wearing lion's skin

Reverse: BAΣIΛEΩΣ ΑΛΕΞΑΝΔΡΟΥ, Zeus Aëtophoros seated left; monogram in wreath in left field, HP monogram below throne.

Diameter: 0 mm
Die Orientation: 0 H
Weight: 0 g
Struck in the name of Alexander III of Macedon, circa 311-300 BC
SC 82.5a; Price 3746.
An AE unit struck c. 285-280 BC in Sardis
Obverse: winged head of Medusa right, snakes in hair

Reverse: bull butting right; BAΣIΛEΩΣ / ΣEΛEYKOY / Ξ

Diameter: -
Die Orientation: -
Weight: -
No notes for this coin
Houghton-Lorber I 21(2), Newell WSM 925, SNG Spaer 23, SGCV II 6852, HGC 9 92a (R1)