Beyond the theological definition, shirk has functioned historically as the charge that organised entire reform movements, and the clearest case is the eighteenth-century alliance between Muhammad ibn Abd al-Wahhab and the Saudi ruling family.
Ibn Abd al-Wahhab, an eighteenth-century scholar in the Arabian peninsula, argued that widespread popular practices, visiting the tombs of saints and prophets to seek intercession, building domed shrines over graves, seeking blessing (baraka) from relics or trees, had reintroduced the very idolatry Islam was sent to abolish, even though practitioners themselves did not consider these acts worship of anyone but God. His alliance with Muhammad ibn Saud in 1744 gave the reform political force, and Wahhabi forces destroyed shrines and tomb domes, including at Karbala in 1802 and repeatedly around Mecca and Medina as Saudi control expanded in the twentieth century, on the ground that elaborate graves and the practices around them constitute or lead to shirk.
The campaign has been consistently contested from within Sunni Islam itself. Ottoman religious authorities, most Sufi orders, and traditionalist scholars across the Hanafi, Shafii and Maliki schools rejected the extension as a departure from centuries of accepted practice, arguing that intermediary requests to the righteous dead, understood correctly, are a request for prayer rather than worship of the deceased, no different in kind from asking a living person to pray for one. The disagreement is not archival: it continues to shape which shrines are permitted, tolerated or demolished in different Muslim-majority states today, and it surfaces whenever contested sites, including some destroyed by later militant groups citing the same reasoning, draw international attention.