In London, the FTSE 100 was up 1.64% at 6,999.77, with energy company Centrica (CPYYY) and financials including Lloyds Banking (LYG) and Royal Bank of Scotland (RBS) among the morning's top gainers. British sterling jumped to a two-month high against the U.S. dollar.
The equities buying spree followed a BBC projection that the Conservatives will take 331 of Parliament's 650 seats compared to 234 for the Labour Party, paving the way for Cameron to end the coalition with the Liberal Democrats and govern alone for the next five years. Polls as late as Wednesday had shown the two main parties in a dead heat, albeit short of an outright majority.
"This is clearly a very strong night for the Conservative party," Cameron told his home constituency early Friday. "I think it has a positive response to a positive campaign about safeguarding our economy, about creating jobs, about our record in government over the last five years but above all our plan for the next five years, based on clear values of wanting to reward work in our country, that those who put in and do their best should find the system is on their side."
In an initial post-election readout, independent London-based analyst and financial blogger Louise Cooper pointed to fears that Ed Miliband's Labour Party would have taken the U.K. back to the 1970s -- "not a great time for U.K. asset prices" -- with more state interventionist rhetoric on rent control and energy price freezes.
"Even if only for personal reasons many city traders, salespeople and fund mangers will have a slightly more springy step today," she wrote, "and markets are driven by emotion."
However, the morning-after endorphin rush was tempered by the growing prospect of a U.K. referendum on a "Brexit" from the European Union by 2017, a key Tory pledge, and an unexpected March decline in industrial production in Germany, Europe's largest economy.
Among Europe's other main indices, the DAX inched up 0.61% to 11,477.52 in Frankfurt, while the CAC 40 added 0.69% to 5,001.25.
In Zurich, Syngenta (SYT) soared more than 17% after rejecting a 41.7 billion Swiss franc ($45 billion) takeover offer from Monsanto (MON), citing "significant execution risks, including regulatory and public scrutiny at multiple levels in many countries."
Syngenta chairman Michel Demaré added that while the current valuation is affected by short-term currency and commodity price movements, "the business outlook is strong," with emerging markets accounting for more than half of sales.
Holcim (HCMLY) was 1.17% higher in in Zurich ahead of today's shareholder vote on the company's planned $39 billion cement merger with France's Lafarge (LFRGY). Earlier this week the deal cleared its last regulatory hurdle when the U.S. Federal Trade Commission signed off on the company's plans to divest North American assets.
In Paris, Lafarge was up 0.16% after an initial decline.
In Helsinki, Nokia (NOK) rose 3.29% following a New York Times report that San Francisco-based ride-sharing company Uber Technologies has submitted a bid for its Here mapping service for as much as $3 billion.
Later today all eyes will be on the U.S., where the Bureau of Labor Statistics is due to release monthly nonfarm payrolls at 8:30 a.m. EDT. Economists polled by Bloomberg News predict that employers in the world's largest economy added 220,000 jobs in April, following an increase of 126,000 in March.
Asian markets were also higher Friday, with the Hang Seng adding 1.05% to 27,577.35 in Hong Kong and the Nikkei advancing 0.45% to 19,379.19 in Tokyo.