Christine Lagarde announced on Thursday that she would step down as the president of the European Central Bank in February, cutting short a turbulent term that spanned a series of economic crises including the Covid-19 pandemic and two energy shocks.

There had been growing speculation and some intrigue that Ms. Lagarde, 70, would leave the post before the end of her eight-year term in October 2027, which would make way for a transition during a politically sensitive time in Europe.

The president of the central bank, which sets interest rates for the 21 countries that use the euro, is chosen by European political leaders. The possibility of a far-right politician winning the French presidential election next spring had led some analysts to speculate that Ms. Lagarde might leave while President Emmanuel Macron was still in office.

Other observers have said that, in the end, Ms. Lagarde’s successor is likely to be chosen through political compromise that would mitigate the influence of any one country.