Möngke, taking command personally late in the decade, has captured many of the Song’s fortified cities along the northern front.

These actions ultimately rendered the conquest a matter of time.

Having waged a series of brilliantly successful campaigns against the Song between 1257 and 1259, Möngke dies on August 11, 1259 near the site of the siege of Fishing Town in modern-day Chongqing.

The Khan’s sudden death halts the war and allows the Song time to revive.

There are several different accounts as to how he perished.

One was that he had been killed by an arrow shot from a Chinese archer during the siege.

Other accounts claim that he was killed by dysentery or even a cholera epidemic.

In any case, his death will ultimately force Hulagu to abort his campaign in Syria and Egypt, and cause another succession crisis, as Kublai and his brother Ariq Böke both claim the Mongol throne.

The ensuing civil war will destroy the unity and invincibility of the Mongol Empire.