An estimated 1,000 people gathered near Waterloo Station and Embankment on Tuesday evening to mark the bank holiday in Albania, observed on November 28, The Evening Standard reported.
Metropolitan Police said they made seven arrests after a breakaway group turned violent.
Offences included assaulting police officers, throwing fireworks and failing to comply with a dispersal order, which was in place until 4am on Wednesday and stretched as far as Soho and Westminster.
Earlier, the police said it estimated "around 1,000 people" had gathered in Belvedere Road as part of a demonstration.
They said a man was arrested for throwing a firework while two cars were stopped because people were "waving Albanian flags through the sunroofs of moving cars".
More arrests were made after a breakaway group ended up in York Road and became "confrontational and aggressive with bottles thrown towards officers".
There was also some disorder in the area around York Road.
Another group has also gathered on Victoria Embankment.
A Section 60 was authorized to give officers additional stop and search powers.
Officers also stopped several convoys of cars traveling into central London with a number of drivers reported for driving offences and several vehicles seized.
The country's Independence Day is a public holiday in Albania marking the date in 1912 when the country's Declaration of Independence established the modern Balkan state.
It is also the same day the country's founding hero Skanderbeg raised the flag, with its trademark black double-headed eagle on a red background, in 1443 and established one of the founding myths of modern-day Albania.
An estimated 140,000 Albanians reside in the UK, a government migration paper in June said.
Last year around 16,000 Albanian citizens applied for asylum in the UK, making up 16 percent of all asylum applicants, according to the Migration Observatory.