Article: Between April 1877 and February 1878, she threatened five times to abdicate while pressuring Disraeli to act against Russia during the Russo-Turkish War, but her threats had no impact on the events or their conclusion with the Congress of Berlin. Disraeli's expansionist foreign policy, which Victoria endorsed, led to conflicts such as the Anglo-Zulu War and the Second Anglo-Afghan War. "If we are to maintain our position as a first-rate Power", she wrote, "we must ... be Prepared for attacks and wars, somewhere or other, CONTINUALLY." Victoria saw the expansion of the British Empire as civilising and benign, protecting native peoples from more aggressive powers or cruel rulers: "It is not in our custom to annexe countries", she said, "unless we are obliged & forced to do so." To Victoria's dismay, Disraeli lost the 1880 general election, and Gladstone returned as prime minister. When Disraeli died the following year, she was blinded by "fast falling tears", and erected a memorial tablet "placed by his grateful Sovereign and Friend, Victoria R.I."

Question: What ended the Russo-Turkish War?
Congress of Berlin