Paris and Milan equities led a retreat across European stock markets Monday as escalating violence across France and street clashes in Italy's financial capital fuelled concerns over elevated debt.
Most sectors were dragged lower, while there was renewed selling of bonds and the euro.
Tech stocks led a rebound on Wall Street on Monday, with the Nasdaq Composite climbing 1.7 percent.
"There was no mistaking that last week was a tough week for the semiconductor and AI trade," said Briefing.com analyst Patrick O'Hare.
Concerns about rising investment costs and whether the vast sums pumped into the sector would see a return dominated sentiment, with investors dumping the stocks and bonds of a company providing computing power for AI firms.
"Staying true to form, though, there is a buy-the-dip bid in those stocks this morning," O'Hare added.
Whether that rebound continues may depend on tech firm earnings and their message about AI investment as more companies report their third-quarter earnings this week.
"Earnings this week will be crucial to broader risk sentiment. In particular, (Facebook parent) Meta is in focus as the first of the five major hyperscalers to report," said Saxo UK investor strategist Neil Wilson.
In Europe, Paris stocks dropped 1.1 percent and Milan fell 1.6 percent.
"European markets reacted anxiously to scenes of severe civil unrest in several countries, highlighted by French President Emmanuel Macron's address acknowledging 'anger and shame' following one of France's worst days of unrest in years," said Patrick Munnelly at Tickmill Group.
Macron on Sunday slammed the "unbridled" violence that erupted alongside cost-of-living demonstrations across the country, as police battled protesters and looters in fresh clashes in Paris.
Nearly 2,400 people were arrested Saturday in unrest that represented some of the worst urban violence in France in years, with almost 1,000 police injured, the interior ministry said.
It comes as the country's lawmakers wrangle over a 2027 budget plan that calls for billions of euros in spending cuts but which keeps France's debt levels extremely high.
In Italy, Prime Minister Giorgia Meloni was holding a security meeting Monday to address the Milan violence, which resembled some of the scenes of chaos and looting in Paris.
Oil prices pulled back Monday on signs that supplies continued to leave the Middle East despite Iran's choke hold on the Strait of Hormuz and ongoing attacks by Yemen's Houthis on key Saudi Arabian crude sites.
US President Donald Trump's decision to waive a new package of energy sanctions on Russia also weighed on oil futures, according to analysts.
Jakarta's stock market sank more than five percent Monday, extending Friday's plunge of more than 11 percent, to close at its lowest level in six years.
It came after index compiler MSCI said it was "no longer appropriate" to maintain the country's emerging-market status, fuelling fears of an exodus of foreign investment.
New York - Dow: UP 0.2 percent at 52,113.84 points
New York - S&P 500: UP 0.9 percent at 7,725.76
New York - Nasdaq Composite: UP 1.7 percent at 26,583.92
Paris - CAC 40: DOWN 1.1 percent at 7,868.05 (close)
Milan - FTSE MIB: DOWN 1.6 percent at 49,086.27 (close)
London - FTSE 100: DOWN 1.1 percent at 10,764.69 (close)
Frankfurt - DAX: DOWN 1.2 percent at 25,319.77 (close)
Tokyo - Nikkei 225: DOWN 0.6 percent at 64,916.70 (close)
Shanghai - Composite: UP 0.4 percent at 3,730.92 (close)
Hong Kong - Hang Seng Index: Closed for a holiday
Brent North Sea crude: DOWN 1.4 percent at $108.36 per barrel
West Texas Intermediate: DOWN 0.7 percent at $100.70 per barrel
Euro/dollar: DOWN at $1.1222 from $1.1236 on Friday
Pound/dollar: DOWN at $1.3316 from $1.3329
Dollar/yen: UP at 158.42 yen from 157.99 yen
Euro/pound: DOWN at 84.25 pence from 84.31 pence
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