First ever English fort - Ft. St. George, Chennai (Madras)

The British, having entered India in 1600 with the sole purpose of doing mercantile trading here succeeded in their goal, keeping their competitors the  Portuguese, the Dutch, and the French quite a distance away from them. They began their trading at Surat, now in the state if Gujarat which was its initial bastion. As their business prospered under the East India company, there arose a necessity for them to have a trade post in Southern India preferably in a place on the west coast so that they could secure its trade lines and commercial interests in the spice trade. Further, they needed a port closer to the Malacca Straits. The location they had in their mind was what is now called Chennai City. At that time chennai was a mere wasteland and having satisfied with the strategic location of the place, they took necessary steps and finally purchased a piece of coastal land originally called Chennairayer Pattinam or Chennai Pattinam from the Vijayanagara chieftain Damerla Chennappa Nayaka based in Chandragiri, now in Andhra. The East India company began the construction of a harbor and a fort to handle their trading activities. Because their project was completed on 23 April 1644 which happened to be St. George's day, the first ever English fort was named in honor of the patron saint of England, St. George. Historically, it was a white town. It served as a home away from home for the officials of the East India Company. Many well known historical British personalities either began their career or had a stint here at Ft. St. George before rising to the position of prominence. Further, this first British fort laid the foundation for what was later to become one of the large cities of India, then called Madras, the capital of Madras Presidency.
Fort St. George, Chennai en.wikipedia.org
 After the construction of the fort, the trading activities were on the increase and it gave a fillip to additional settlements and better trading opportunities. Nobody ever thought what was originally an uninhabited land would become a hub of trading activities. Thus, it culminated in the development of small township (Black Town) around the fortress that included some fishing villages.The fort currently houses the Tamil Nadu legislative assembly and other official buildings.
Fort St. George, Chennai  under the Britishdaily.indianroots.com
Fort is a sturdy one with six-meter high walls and a moat around it that remarkably withstood a number of vigorous assaults in the 18th century. The French, the major competitor on the east coast and in South India took possession of the fort from 1746 to 1749 for a brief spell. Later, in accordance with the Treaty of Aix-la-Chapell, it was restored to the Great Britain.
 Ft. St.Geoge, Chennai www.brokeragesdaytrading.com
With sustained progress in mercantile trade activities and under able, effective management of company affairs, the British established their supremacy in this part of India. They became a force to reckon with. They succeeded in exerting their influence over the Carnatic and to keep the ruler of Arcot-the Nawob and Srirangapatna - both Hyder Ali and his son Tipu under check. They did face threats from the French who sided with Hyder Ali and Tipu  and further, they never failed to keep the French forces based at Pondicherry at bay.
St.Mary's Church, Fort St.George, Chennai. muthusamy.aminus3.com
Interior of St Mary's Church. within Fort St. George, Chennai.
murshidabad.net
There was an old 148 ft tall Flagstaff, made entirely of teak wood. and since 1994 a replica of the original teak mast has been in place. Though the original flagstaff is no more to be seen, its relics are still visible. It is believed to be the 2nd highest in the country. It was erected by Governor Yale during his tenure in the year 1688 (June).
St. George  Fort, Chennai and Flag staff. sriramv.wordpress.com
The Fort was and is now a seat of power!!  It presently houses
 the administrative headquarters for the legislative assembly of Tamil Nadu state, the secretariat and a garrison of troops in transit to various locations in South India and the Andaman. The fort has many relics of the Raj Era, including the portraits of many old Governors of the Madras Presidency. The fort is being managed by the  ASI - Archaeological Survey of India.

The church and the building that housed the museum were completed in 1795. Once on the first floor, Madras bank was functioning and also the public exchange. It served as a place for public meetings, lottery draws and occasional entertainment.

Ref:

https://en.wikipedia.org/wiki/Fort_St._George,_India