PARIS — French voters have given a broad leftist coalition the most parliamentary seats in a pivotal legislative election that has kept the far right from power but has put France in the unprecedented position of having no dominant political bloc in parliament.

While a fractured parliament is not uncommon in Europe, France has not experienced that in its modern history. That sends the country into uncharted territory that will involve tense negotiations to form a new government and name a prime minister, who focuses on domestic policy and shares power with the president.