Daniel 1:21

Daniel : the prophet who wrote the book of Daniel,son of David and Abigail,head of clan (Ithamar Levi) who pledged to obey God's law,prophet who wrote the book of Daniel

Koresh : the Persian king of Babylon known as Cyrus the Great (OS)

Daniel 2:10

Kasdim : the inhabitants of Chaldea.
(32° 32´, 44° 25´); (30° 57´, 46° 6´); (31° 49´, 35° 17´); (32° 32´, 44° 25´); (30° 57´, 46° 6´)

Ur-Kasdim : a town of lower Mesopotamia about 230 km SE of old Babylon,father of Eliphal / Eliphelet, one of David's military elite
(32° 32´, 44° 25´); (30° 57´, 46° 6´); (31° 49´, 35° 17´); (32° 32´, 44° 25´); (30° 57´, 46° 6´)

Daniel 10:2

Daniel : the prophet who wrote the book of Daniel,son of David and Abigail,head of clan (Ithamar Levi) who pledged to obey God's law,prophet who wrote the book of Daniel