Marduk’s main cult place was the city of Babylon. , which became the religious centre of Mesopotamia during the second and first millennia BCE (see various contributions in Cancik-Kirschbaum et al. 2011). Marduk’s main temples were located in Babylon.

1 BCE

Marduk was moved to “Jupiter” and then “God”

https://www.newworldencyclopedia.org/entry/Marduk

Marduk (Sumerian for “solar calf”; Biblical Merodach) was the name of a late generation god from ancient Mesopotamia and patron deity of the city of Babylon. When Babylon became the political center of the Euphrates valley in the time of Hammurabi (eighteenth century B.C.E.), Marduk rose to the head of the Babylonian pantheon, a position he fully acquired by the second half of the second millennium B.C.E. He was also referred simply as “Bel,” meaning “Lord,” or Bel-Marduk. Marduk was thus the chief deity of the Babylonian Empire during the period of Jewish exile in Babylon (sixth-fifth centuries B.C.E.). It was Marduk whom Cyrus the Great of Persia credited with the inspiration to allow the Jews to return to Jerusalem and rebuild the Temple of Yahweh. Marduk’s association with the solar system‘s largest planet led indirectly to its being named Jupiter, after the Roman god who occupied Marduk’s place in the pantheon.

 Assur, the patron deity of the city of Assur from the late Bronze Age, was in constant rivalry with the patron deity of Babylon, Marduk. Worship was conducted in his name throughout the lands dominated by the Assyrians. With the worship of Assur across much of the Fertile Crescent, the Assyrian king could command the loyalty of his fellow servants of Assur.