Bangalore lies in the southeast of the South Indian state of Karnataka. It is in the heart of the Mysore Plateau (a region of the larger Precambrian Deccan Plateau) at an average elevation of 920 m (3,018 feet). It is positioned at [show location on an interactive map] 12.97° N 77.56° E and covers an area of 741 km² (286 mi²). The majority of the city of Bangalore lies in the Bangalore Urban district of Karnataka and the surrounding rural areas are a part of the Bangalore Rural district. The Government of Karnataka has carved out the new district of Ramanagaram from the old Bangalore Rural district.

The topology of Bangalore is flat except for a central ridge running NNE-SSW. The highest point is Doddabettahalli, which is 962 m (3,156 ft) and lies on this ridge. No major rivers run through the city, though the Arkavathi and South Pennar cross paths at the Nandi Hills, 60 km (37 mi.) to the north. River Vrishabhavathi, a minor tributary of the Arkavathi, arises within the city at Basavanagudi and flows through the city. The rivers Arkavathi and Vrishabhavathi together carry much of Bangalore's sewage. A sewerage system, constructed in 1922, covers 215 km² (133 mi²) of the city and connects with five sewage treatment centers located in the periphery of Bangalore.

After centuries of the rule of the Western Gangas, Bangalore was captured by the Cholas in 1024 which later passed on to the Chalukya-cholas in 1070. In 1116 the Hoysala Empire, overthrew the Cholas and extended its rule over Bangalore. Modern Bangalore was founded by a vassal of the Vijayanagara Empire, Kempe Gowda I, who built a mud fort and a Nandi Temple in the proximity of modern Bangalore in 1537. Kempe Gowda referred to the new town as his "gandu bhoomi" or "Land of Heroes".

Within the fort, the town was divided into smaller divisions called petes. The town had two main streets: Chickkapete Street, which ran east-west, and Doddapete Street, which ran north-south. Their intersection formed the Doddapete Square the heart of Bangalore. Kempe Gowda's successor, Kempe Gowda II, built four famous towers that marked Bangalore's boundary. During the Vijayanagara rule, Bangalore was also referred to as "Devara-yanagara" and "Kalya-napura" ("Auspicious City"). After the fall of the Vijayanagara Empire, Bangalore's rule changed hands several times. In 1638, a large Bijapur army led by Ranadulla Khan and accompanied by Shahji Bhonsle defeated Kempe Gowda III and Bangalore was given to Shahji as a jagir. In 1687, the Mughal general Kasim Khan defeated Ekoji, son of Shahji, and then sold Bangalore to Chikkadevaraja Wodeyar (1673-1704) of Mysore for 300,000 rupees. After the death of Krishnaraja Wodeyar II in 1759, Hyder Ali, Commander-in-Chief of the Mysore Army, proclaimed himself the de facto ruler of Mysore. The kingdom later passed to Hyder Ali's son Tippu Sultan, known as the Tiger of Mysore. Bangalore was eventually incorporated into the British East Indian Empire after Tippu Sultan was defeated and killed in the Fourth Anglo-Mysore War (1799). The British returned administrative control of the Bangalore "pete" to the Maharaja of Mysore, choosing only to retain the Cantonment under their jurisdiction. The 'Residency' of Mysore State was first established at Mysore in 1799 and later shifted to Bangalore in the year 1804. It was abolished in the year 1843 only to be revived in 1881 at Bangalore and finally to be closed down in 1947 with the departure of the British. The British, found it easier to recruit employees in the Madras Presidency and relocate them to cantonment area during this period. The Kingdom of Mysore relocated its capital from Mysore city to Bangalore in 1831. Two important developments during this period contributed to the rapid growth of the city: the introduction of telegraph connections and a rail connection to Madras in 1864.

The name Bangalore is an anglicised version of the city's name in the Kannada language, Bengalu-ru. The earliest reference to the name "Bengaluru" was found in a 9th century Western Ganga Dynasty stone inscription on a "vi-ra kallu" (literally, "hero stone", a rock edict extolling the virtues of a warrior). In this inscription found in Begur, "Bengaluru" is referred to as a place in which a battle was fought in 890. It states that the place was part of the Ganga kingdom until 1004 and was known as "Bengaval-uru", the "City of Guards" in Old Kannada. An article, published in The Hindu, states:

An inscription, dating back to 890 CE, shows Bengaluru is over 1,000 years old. But it stands neglected at the Parvathi Nageshwara Temple in Begur near the city...written in Hale Kannada (Old Kannada) of the 9th century CE, the epigraph refers to a Bengaluru war in 890 in which Buttanachetty, a servant of Nagatta, died. Though this has been recorded by historian R. Narasimhachar in his Epigraphia of Carnatica (Vol. 10 supplementary), no efforts have been made to preserve it.