The short answer is France. The slightly longer answer is that there are a lot of 'buts' there. Bear with me.
The date typically given for universal male suffrage in France is 1792 (with the decree of 12 August, to be precise) which removed any property or income restrictions on the franchise but still excluded the unemployed and servants. So it was close but not quite universal. The Constitution of 1793 did enshrine universal male suffrage but that constitution was never actually implemented. The Constitution of 1795 restored a property requirement (albeit a minimal one) but this was removed in the Constitution of 1799. The latter was the first to be extend the right to vote to all males over 21 but this was the beginning of Napoleon's Consulate and I don't believe that free elections were ever actually held.
Now all these were progressive documents that abolished restrictions based estates or religion and expanded the electorate but the first time that a French national election was actually held under universal suffrage was probably 1848. It was then restricted again in 1850 before being restored under the Second Empire [1]. The Third Republic finally adopted universal male suffrage for good in 1875.
Reading back over the above I realise that I haven't actually answered your question. It very much depends on what date you pick – take one from the revolutionary decade and France is the first country by some distance (and it certainly pioneered the concept); take the later dates and France is still fairly early (1848), but maybe not the first, or actually relatively late to the party (1875).
[1] The attitude by the end of the Second Republic can be summed up by a French Prefect as "the communists cannot be offered the possibility of becoming kings through the ballot. Society must not commit suicide". But Louis Napoleon found the legitimacy provided by universal male suffrage useful and so regular elections/plebiscites were a feature of the Second Empire.
Sources:
[Edit: Formatting]