My answer noted that every society in history has had some form of religion. Those that professed monotheism (one God) were referring to the same God. Moreover, in the religions whose earthly origins date back to Abraham, Sarah, and Hagar; namely Judaism, Christianity and Islam, Allah is the Arabic word for God. Christians in France call God Dieu and so forth.
What is of some interest here is that early Judaism’s monotheism had two words for God. Northern biblical Hebrew-speakers referred to Aloya/Elohim while the southern speakers of Hebrew called God Yahweh. Christianity, in its earliest form, emerged from Judaism.
Bethlehem was in the south so God would be Yahweh, but as Christianity spread, the same God among monotheists took on many names.
There has been some questions raised about the the incoming president’s closing words in the oath of office: “So help me God.” By using “God,” are we leaving out other non-Jewish-Christian-Muslim US citizens in a nation where we separate “church and state”? Not really, since most US citizens are Jewish, Christian, or Muslim, and those who are not will probably not object until they have won the presidency and must take the oath. This has not happened for 250 years.
