3 to 4 billion drown to death
Genesis 6 - 8
Mankind's roughly 1,650 years of existence before the flood came with incredibly long lifespans. How long did folks live? The ideal conditions existing on earth led to ten Bible patriarchs living an average of 850+ years! The long lives, however, coupled with being cut off from God, caused a continuous moral decay that led people to focus entirely on fulfilling their own lusts (Genesis 6:5 - 6).
God's solution to stem the earth's ever-increasing tide of evil was to simply wipe out all those alive with a flood and restart humanity with just eight individuals. Some modern mathematical models project that earth's population, at the time of Noah's flood, could have easily been between 3 to 4 billion (Biblical Basis for Modern Science, Chapter 15)!
c. 913 - 910
500,000 Israelites killed by Jews
King Jeroboam, toward the end of his reign as Israel's first post-split ruler, decides to battle the Kingdom of Judah in an all-out war. His army of 800,000 fighting men is double the size of his rival King Abijah's forces.
Jeroboam's sneak attack on Abijah's army, forcing him to fight on two fronts, is initially successful as it causes panic and confusion among the Jewish fighters. In desperation, the Jews cry out to God for help. The Lord not only hears their prayers but also turns the tide of war against Jeroboam. In the end, the Kingdom of Israel suffers its worst numeric defeat ever, losing 500,000 men or 62% of its army in the civil war!
185,000 receive instant death
2Kings 18 - 19, Isaiah 37
The Assyrian Empire's King Sennacherib decides to send an army of 185,000, led by three of his top men, to Jerusalem. Their goal is to intimidate Judah's King Hezekiah into unconditionally surrendering or else have the entire city destroyed. The Assyrians, however, make the fatal mistake of mocking God directly (2Kings 19:22 - 28).
The Assyrian's chief field commander, in a voice loud enough so that all those on Jerusalem's wall could hear, proudly yells the following toward the city.
And do not let Hezekiah make you trust in the Lord, saying, 'The Lord will surely deliver us . . .'
Who among all the gods of the countries have delivered their countries out of my hand, that the Lord should deliver Jerusalem out of my hand? . . . Do not let your God in Whom you trust deceive you . . . (2Kings 18:30, 35, 19:10).
God's answer to Hezekiah's humble cry for help leads to the greatest military defeat in history! At night, the Angel of the Lord executes all 185,000 troops camped around Jerusalem. They die so quickly that not a single arrow is fired in defense. The city, when the morning dawns, is stunned to see nothing by corpses!
c. 1380 - 1350
140,000+ killed in civil war
A horrendous act, not long after the death of Joshua, takes place in the Benjamite town of Gibeah. Several men in the city brutally abuse and rape a Levitical priest's wife so bad that it leads to her death (see Judges 19 - 21). News of the evil act spreads quickly and soon a 400,000-man army from the other eleven tribes forms (Judges 20:2). They demand the tribe of Benjamin hand over the wicked Gibeah criminals for justice (see Genesis 9:6, Deuteronomy 22:25 - 29, etc.).
Benjamin, for reasons the Bible does not record, refuses to expel those who had committed such heinous crimes. A civil war quickly ensues.
After three days of battles the Israelites lose at least 40,030 fighting men (Judges 20:21, 24 - 25, 31) while the tribe of Benjamin experiences 25,100 war causalities (verse 35). Israel, after defeating the skillful Benjamite warriors, then kills every woman, child, and any remaining men within the territory of Benjamin (verse 48). When the killing finally stops, only 600 men are left alive in the punished tribe (verse 47).
c. 874 - 853
127,000 Syrians killed by Ahab
Because of the arrogance of King Benhadad (1Kings 20:2 - 6), as well as Syria's general disrespect for God (verse 28), the Lord decides to deliver them over to Israel's notorious King Ahab. The Israelites, in a single day, kill 100,000 Syrian footmen (verse 29). The remnants of Benhadad's army flees to Aphek where a collapsed wall kills another 27,000 (verse 30)!
120,000 Jews killed by Israel
King Pekah of Israel decides to enter into a civil war with King Ahaz of Judah. The Lord, because the Jews had forsaken him (2Chronicles 28:6), allows 120,000 of Ahaz's troops to be killed in a single day!
c. 1010 - 970
70,000 killed as punishment
King David, during his reign, foolishly initiates a census to discover how many fighting men existed in Israel. God allows him to choose which of three great punishments to receive for his sin. The king chooses to have three days of pestilence come upon the land. God, utilizing an angel, had it kill 70,000 Israelites before halting it as it prepared to strike Jerusalem.