Why was control of constantinople important

Fall of Constantinople, (May 29, 1453), conquest of Constantinople by Sultan Mehmed II of the Ottoman Empire. The dwindling Byzantine Empire came to an end when the Ottomans breached Constantinople’s ancient land wall after besieging the city for 55 days. Mehmed surrounded Constantinople from land and sea while employing cannon to maintain a constant barrage of the city’s formidable walls. The fall of the city removed what was once a powerful defense for Christian Europe against Muslim invasion, allowing for uninterrupted Ottoman expansion into eastern Europe.

determination

"the sepoy rebellion was the result of many, many influences and stressors on the cultures of india living under british rule. in britain, it's called the sepoy mutiny on the indian mutiny, but in india, it's called the first war of independence.

the main reason is concerned to the british paramountcy , the belief in british   dominance in india political, economic and cultural life had been introduced in india about 1820."

"they were forced to grow crops that benefited the colonizing nations instead of feeding their own people."