Wikipedia has a piece on decimalisation in Europe as follows:
Formal decimalisations
Europe
Russia converted to a decimal currency under Tsar Peter the Great in 1704, with the ruble being equal to 100 kopecks, thus making the Russian ruble the world's first decimal currency.
France introduced the franc in 1795 to replace the livre tournois, abolished during the French Revolution. France introduced decimalisation in a number of countries that it occupied during the Napoleonic period.
Sweden introduced decimal currency in 1855. The currency riksdaler was divided into 100 öre. The riksdaler was renamed krona in 1873.
The Austro-Hungarian Empire decimalised the Austro-Hungarian gulden in 1857, concurrent with its transition from the Conventionsthaler to the Vereinsthaler standard.
Spain introduced its decimal currency unit, the peseta, in 1868, replacing all previous currencies.
Cyprus decimalised the Cypriot pound in 1955, which comprised 1,000 mils, later replaced by 100 cents.
On Decimal Day, 15 February 1971, the United Kingdom decimalised the pound sterling and the Republic of Ireland decimalised the Irish pound.
Malta decimalised the lira in 1972.