FIGHT AGAINST THOSE WHO DON'T BELIEVE IN ALLAH & MUHAMMAD, OTHERWISE CONVERT OR PAY JIZYA - ISLAMIC TAX AS FORM OF HUMILIATION

A quick summary:
Muslims are instructed to support the Caliphate to fight against non-Muslims and conquer to convert the land under Islamic sharia law.

Quran 9:29
Fight those who do not believe in Allah or in the Last Day and who do not consider unlawful what Allah and His Messenger have made unlawful and who do not adopt the religion of truth from those who were given the Scripture - until they give the jizyah willingly while they are humbled.

Contemporary Islamic scholar: Ibn Kathir Tafsir:

A STORY OF UMM QIRFA WAS BRUTALLY MURDERED UNDER ISLAMIC ARAB PROPHET MUHAMMAD'S LEADERSHIP.

Umm Qirfa was an old Arab woman contemporaneous to Muhammad, the prophet of Islam. She was also a chief who belonged to a pagan tribe named Banu Fazara at Wadi Al-Qurra.

She was brutally killed during Muhammad and his followers raided her tribe and overpowered them. The incident took place almost six years after Muhammad’s Hijra (هِجْرَة Migration) to Medina in 622 AD.

Reference: Al Tabari Volume 8: Page 95-96