The sun rose once more on the British Empire today as Britain took control of its breakaway colony of Rhodesia with the arrival of the British Governor, Lord Soames.

When Soames set foot on Rhodesian soil at 2:15 p.m., local time it signaled the country's return to legality after 14 years, one month and one day of unrecognized independence under white-minority control. For Britain, on whose far-flung empire it used to be said "the sun never set," it marked the first time in 11 years that it has had charge of a colony in Africa.

The return to colonialism is to be hort-lived, however, since under the terms of a Rhodesian independence settlement being worked out in London, Soames will pull out soon after supervising elections for a new government. The date, probably in March, is still to be set in negotiations in London involving the Patriotic Front guerrllas, who have been fighting a war for power for the last seven years.

Soames and a team of several hundred British officials are to have all executive and legislative authority, ruling through civil servants of former prime minister Abel Muzorewa's government, which dissolved itself yesterday to make way for British control.

In an address broadcast to the nation tonight, Soames said, "It will be no part of my job to make decisions or make changes" except to carry out the elections.

"Matters affecting the future of your country will be for the new government to decide when it is formed after the elections," he added.

His arrival, he said, marks the beginnings of the country's return to normality. As a result of the return to British control, Britain today lifted economic sanctions against Rhodesia, long a sore point with the 230,000 whites among the 7 million population. The United States is expected to do so shortly.

The governor's arrival presents an unusual problem for Britain since it means Soames is now technically in charge of Salisbury forces that are fighting a war against the Patriotic Front guerrillas. British Foreign Secretary Lord Carrington is still negotiating with the guerrillas over final details of a cease-fire, the last element to be resolved before a settlement that already has been accepted by Muzorewa.

Soames' taking power before signing of the agreement is regarded as Carrington's most serious gamble in pressuring the Front. Carrington has frequently used such brinksmanship successfully during the 14-week conference and most observers expect the guerrillas to accept Britain's terms, perhaps with slight modifications, shortly.

British Prime Minster Margaret Thatcher has assured Parliament that none of the 700 British troops that make up the bulk of a planned 1,200-member Commonwealth cease-fire monitoring force will be airlifted to Rhodesia until a full settlement is reached.

It is also believed that the United States, which is to provide jet transports to move helicopters, trucks and other equipment for the monitoring force, will not allow the planes to land in Salisbury before there is a settlement.

Soames said he hoped a cease-fire would be reached soon.

"This will not be an easy period for any of us," he said. "In emerging from a long and bitter war, there will be many difficulties. But together we must overcome them, looking to the future rather than to the past. For a war-weary country, the prize is great."

Despite the symbolic significanes of the governor's takeover, there was little outward sign of change in Salisbury, the capital. As Soames' limousine drove into the grounds of Government House, his official residence, the British flag was unfurled without ceremony.

That was the only Union Jack readily in evidence on an official building, however, as the British appeared to go out of their way not to affront white Rhodesians with the restoration of their rule.

The white manager of Salisbury airport, asked why the five-color Zimbabwe-Rhodesian flag was continuing to fly after Soames' arrival, said: 'I'll fly whatever bloody flag I want to."

Soames's takeover of power as governor marked the first time in the 89-year history of Rhodesia that Britain has formally been in control of the country. h

From its founding by British entrepreneur Cecil Rhodes in 1890 until 1923 it was run by Rhodes's British South Africa Co. In 1923, Rhodesians voted to become a self-governing colony with Britain maintaining a thin veneer of control until former prime minister Ian Smith unilaterally and illegally declared independence in 1965.

The Herald, Rhodesia's main English-language newspaper, said in an editorial today: "No one in this country will regard the arrival of Lord Soames as an occasion for rejoicing.

"Few could have imagined 14 years ago," it added, "that it would all end this way, with not only a renunciation of the sovereignty we assumed on Nov. 11, 1965, but also the acceptance of a status more lowly than it was before."

Soames' arrival was a low-key affair with the airport barred to all persons except invited officials, press and scheduled travelers.

Amid the normal airport announcements, the public-address system bared out at 2:10 p.m.: "The Royal Air Force announces the arrival of Ascot 1175 from London Heathrow."

Muzorewa led a delegation of his former ministers to greet Soames at the airport. No Patriotic Front members were invited. Smith boycotted the occasion, preferring to remain in his office.

The ceremony only lasted about 15 minutes as Soames inspected an honor guard of the British South African Police, Rhodesia's police force which will be responsible for law and order during the transition.

Along the drive from the airport to Government House, small groups of demonstrators, of varying political views, welcomed the governor.

Supporters of Muzorewa waved banners praising him as a peacemaker and for bringing the country to legality.

The confused political history of Rhodesia was in evidence further down the road as some whites waved a green and white flag of the Rhodesian Republic declared by Smith in 1969 while others held the old colonial flag with a Union Jack in the corner.

About 200 demonstrators favoring the return to legality were at Government House to cheer Soames. One said, "It's great. We've been living in an illegal banana republic for 14 years."

There was a touch of history in the occasion as Sir Humphrey Gibbs, 77, the last British governor, was among the crowd.

Section Officer Chikovore, a black member of the police who had run down the last Union Jack at Government House 10 years ago when Gibbs left, unfurled today's flag marking the beginning of the planned short-lived second British Empire in Africa.