Karbala is most renowned as the site of the Battle of Karbala in 680 CE (61 AH), a pivotal event where Imam Hussein ibn Ali, the grandson of Prophet Muhammad, was martyred, profoundly shaping Shia Islam.

Historically, the area around Karbala was known as Al-Ghadiriyah and was a fertile agricultural region before the Islamic era, later gaining religious significance due to the martyrdom of Imam Hussein.

Karbala is situated approximately 100 kilometers southwest of Baghdad, Iraq, on the edge of the Arabian Desert, benefiting from its location near a branch of the Euphrates River, which is crucial for its agriculture.

The most significant landmark is the Imam Hussein Shrine, a magnificent complex featuring a golden dome and minarets, built over the tomb of Imam Hussein, serving as a primary pilgrimage destination for millions of Shia Muslims annually.

Adjacent to the Imam Hussein Shrine is the Al-Abbas Shrine, equally grand, housing the tomb of Al-Abbas ibn Ali, Imam Hussein's half-brother and standard-bearer, revered for his bravery during the Battle of Karbala.

Karbala hosts the annual Arba'een pilgrimage, one of the largest peaceful gatherings in the world, where millions of Shia pilgrims converge to commemorate the 40th day after Imam Hussein's martyrdom.

The city of Karbala has experienced significant population growth, particularly since 2003, with its metropolitan population estimated to be well over 1.2 million, driven by pilgrimage-related migration and economic opportunities.

The economy of Karbala is overwhelmingly dominated by religious tourism, with countless hotels, guesthouses, restaurants, and souvenir shops catering to the millions of pilgrims who visit the holy shrines throughout the year.

Beyond religious tourism, Karbala remains an important agricultural center, utilizing its proximity to the Euphrates to cultivate dates, citrus fruits, and other crops, sustaining a vital local food supply.

Karbala has historically been a focal point for political and religious dissent, particularly during periods of Sunni-majority rule in Iraq, and continues to be a significant center of Shia political and religious influence.

Local traditions in Karbala are deeply intertwined with Shia Islamic practices, including elaborate mourning rituals (Aza'dari), recitations of elegies (Latmiyat), and dramatic re-enactments of the Battle of Karbala (Tazieh) during Muharram.

While the city's historical and religious core is not formally designated as a UNESCO World Heritage Site, there have been ongoing efforts and proposals to list it due to its outstanding universal value.

The city intensely observes Ashura, the 10th day of Muharram, marking the anniversary of Imam Hussein's martyrdom, with solemn processions, self-flagellation rituals, and a profound atmosphere of grief and devotion.

During the Ottoman era, Karbala became a semi-autonomous principality and continued to flourish as a religious center, facing periodic challenges but maintaining its sanctity, which further solidified its status in the modern Iraqi state.

The population of Karbala is overwhelmingly Shia Muslim, reflecting its historical and religious significance as a spiritual capital for the faith, with a smaller presence of other religious minorities.