Yes, the people of Norway loved Märtha.
Märtha (Sofia Lovisa Dagmar Thyra) was born a princess of Sweden and grew up with her sisters, Princess Margaretha and Princess Astrid, and her younger brother, Prince Carl. She was the most self-assured of the group and eyecatcher at many balls.
During the 1928 Olympic Games, she became engaged to her cousin (!), Prince Olav. [Märtha's mother (Ingeborg of Sweden) was a sister of Olav's father (King Haakon VII of Norway)].
Their marriage in 1929 marked an improvement in relations between Norway and Sweden. Twenty-five years earlier, the union between Norway and Sweden had been dissolved, and Märtha’s grandfather, Oscar II of Sweden, had been deposed from the Norwegian throne.
At that time, Märtha distinguished herself from other female members of royal families by delivering countless speeches; within the limits of her position, she was quite emancipated.
When World War II broke out in 1940, it was Märtha who called on Norwegian women to participate in the mobilization to defend Norway.
From the U.S., the Crown Princess was very active in her efforts on behalf of occupied Norway.
Upon her return to Norway, she received a hero’s welcome and was called “the mother of the nation,” thanks to all her efforts. The impact she had on the Norwegian people was comparable to that of Princess Diana on the British people in the 1980s and 1990s.
What about her sisters and brother?
Princess Margaretha (Margaretha Sofia Lovisa Ingeborg) married Prince Axel of Denmark in 1918. After the death of her sister Märtha in 1954 she regularly assisted her brother-in-law, King Olaf V of Norway. She died in 1977.
Princess Astrid (Astrid Sofia Lovisa Thyra) became engaged to Crown Prince Leopold, son of King Albert I of Belgium.
The couple married in Sweden on November 4, 1926; six days later, on November 10, a second wedding ceremony took place in Belgium.
There was concern within the royal family because of her Lutheran faith. A few years after her marriage, she converted to Roman Catholicism.
Upon the death of Albert I in 1934, her husband became King Leopold III and she herself became Queen of Belgium.
In 1935, at the age of 29, our Queen was killed in a car accident in Küssnacht am Rigi, Switzerland, where the couple had been on an incognito outing under the name Renard before returning home.
Her unborn fourth child also died with her, while her other children had traveled home by train the night before.
Küssnacht donated the land where the accident occurred to Leopold, on which he had a chapel built in her memory.
Leopold III will remarry in 1941 to a commoner, Lilian Baels, as I already mentioned in my earlier reply.
Astrid gave the dynasty the future kings of Belgium, Baudouin and Albert II, and Grand Duchess Josephine Charlotte of Luxembourg.
Prince Carl (Carl Gustaf Oscar Fredrik Christian), for some time, was considered a potential suitor for the Dutch Crown Princess (future queen) Juliana. In 1934, an arranged meeting between the two took place at the British court. According to the Dutch envoy in London, however, Juliana displayed so little tact and sense of etiquette during the meeting that Prince Charles withdrew from the match after just the first meeting.
In 1937, he renounced his claim to the Swedish throne to marry the divorced Swedish Countess Elsa von Rosen. He was no longer Prince of Sweden but simply Carl Bernadotte.
In 1938, his brother-in-law, King Leopold III, admitted him into the Belgian nobility with the personal title of prince and the title of count/countess for his descendants. His marriage ended in divorce in 1951.
His second marriage in 1954 to Ann Margareta Larsson also ended in divorce in 1961.
In 1978, he married for the third time, this time to Kristine Rivelsrud.
He died in 2003.