Simplify the following text for a Grade 17 native English-speaking person.
Original: Ignatyev was trying to dispel British misgivings about Russiaâ s assumed role of a protector of the Orthodox Slavs being but a disguise of its drive to take over the Black Sea Straits and Constantinople itself and thus â `` as Prime Minister Disraeli feared â `` potentially threaten the vital Mediterranean routes to British India .
Simplified: Ignatyev was trying to dispel British misgivings about Russiaâ s assumed role of a protector of the Orthodox Slavs being but a disguise of its drive to take over the Bosporus and Constantinople itself and thus â `` as Prime Minister Disraeli feared â `` potentially threaten the vital Mediterranean routes to British India .