U.S. stocks jumped on Monday, with the Nasdaq Composite rising to its highest level since March 2000 and the price of oil falling to its lowest in more than a year, as geopolitical tensions eased.
Dollar General jumped after the discount retailer offered $8.95 billion for Family Dollar Stores, challenging a bid from Dollar Tree.Monster Beverage fell after Jefferies Group downgraded the stock to hold from buy. Shares of Urban Outfitters advanced ahead of the retailer's earnings release after Monday's close.
The CBOE Volatility Index, a measure of investor uncertainty, fell 6.3 percent to 12.32.
Russia said a dispute over its convoy of humanitarian aid to Ukraine had been settled, and a Ukrainian official said more than five hours of discussions in Berlin had brought about "moderate progress," according to media reports.
The development "points to some degree of cooperation, which is probably a constructive environment for global and domestic equities," said Jim Russell, senior equity strategist for US Bank Wealth Management.
The Federal Open Market Committee meeting in the middle of September is the "next really big capital-markets event, until then, geopolitical events will have a heavy influence, especially the Russia and Ukraine conflict, when something happens, that seems to really be lighter fluid, today being a good example," Russell added.
And, Iraqi and Kurdish troops reportedly reclaimed control of the Mosul Dam after increased U.S. airstrikes aimed to help them during the weekend.
"It appears the Kurds are making progress in taking back the dam in Mosul, so the Iraq story too is playing a role here," Art Hogan, chief market strategist at Wunderlich Securities, said of OPEC's second-largest producer of crude.
Sensata Technologies Holding said it would pay $1 billion to acquire the Schrader group of companies, and Ingersoll-Rand said it would purchase Cameron International's centrifugal compression business for $850 million.
The National Association of Home Builders reported its month index of confidence among those building single-family homes rose 2 points to 55, coming in better than expected.
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"It's a forward looking survey, and we've seen that move in a positive direction for three months in a row. But it's a B-list piece of economic data, more important are housing-start numbers later in the week," said Hogan.
The advanced 16.68 points, or 0.9 percent, to 1,971.74, with industrials leading sector gains and utilities the poorest performing of its 10 major industry groups rising.
"With the S&P taking out 1,950 and then the 50-day moving average on the upside, it was enough to change a lot of minds, especially those that are underperforming due to the geopolitical issues that kept them away from buying just above key support at 1,900," Elliot Spar, market strategist at Stifel, Nicolaus & Company, wrote in afternoon commentary.
Climbing to its highest level in more than 14 years, the Nasdaq gained 43.39 points, or 1 percent, to 4,508.31.
For every stock falling, roughly four gained on the New York Stock Exchange, where nearly 605 million shares traded. Composite volume cleared 2.6 billion.
On Friday, U.S. stocks ended the week mixed in below-average trade volume amid news of fresh conflict between Russia and Ukraine.
"U.S. stocks rebounded as markets likely considered that slowing global economic growth will keep interest rates low for some time, and ongoing geopolitical tensions eased somewhat," E. William Stone, chief investment strategist at PNC Financial Services Group, noted in emailed commentary.
—By CNBC's Kate Gibson
Coming Up This Week:
8:30 a.m.: CPI
8:30 a.m.: Housing starts
8:30 a.m.: Building permits
7:00 a.m.: Mortgage applications
2:00 p.m.: FOMC minutes
8:30 a.m.: Jobless claims
10:00 a.m.: Existing home sales
10:00 a.m.: Philadelphia Fed survey
10:00 a.m.: Leading economic indicators
1:00 p.m.: $16 billion 5-year TIPs auction
Earnings: Ann, Foot Locker, Royal Bank of Canada
10:00 am Fed Chair Janet Yellen at Jackson Hole
2:30 pm European Central Bank President Mario Draghi