How did David eventually become king over all of Israel?

Answer 1

By war.

Answer 2

After the death of King Saul, David moved to Hebron, where the older men of Judah anointed him as king over their tribe in 1077 B.C.E., when he was 30 years old. Saul's son Ish-bosheth was made king of the other tribes. About two years later, however, Ish-bosheth was assassinated, his assailants bringing his head to David hoping to receive a reward, but they too were put to death like the pretended killer of Saul. (2Sam 2:1-4, 8-10; 4:5-12) This paved the way for the tribes who had till then supported Saul's son to join Judah, and in time, a force numbering 340,822 rallied and made David king of all Israel. (2Sam. 5:1-3; 1Chronicles 11:1-3; 12:23-40)

Answer 3

Before defeating Goliath, the young David was appointed as armor-bearer and as a musician to play in front of King Saul (1 Samuel ch.16). Still earlier, David had been anointed by Samuel, meaning that he would later become the next king. After defeating Goliath (1 Samuel ch.17), Saul appointed David to lead his army (1 Samuel ch.18). After Saul died (1 Samuel ch.31), the people gradually accepted David as king over all the Israelite tribes.

See also:

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Accuracy of the Hebrew Bible

Answer 4

In the Book of Samuel, David was chosen by God and anointed by Samuel to be King Saul's successor. The reason David was accepted as king was his defeat in single combat of the Philistine giant Goliath.
It seems that the slaying of Goliath was so improbable that the Book of Chronicles, which was a later rewrite of the Deuteronomic History, does not even mention it.

Answer 5

When Saul died (1 Samuel ch.31), at first only the Tribe of Judah supported David as the next king (2 Samuel ch.2). The others gave backing to Saul's son Ish Bosheth (ibid); and this state of affairs lasted seven years, during which more and more influential people gradually came over to David's side. By the end of the seven years, David was able to take the helm of monarchy over all twelve Israelite Tribes, until his death thirty-three years later. See also the Related Link.

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