Short answers, pulled from the story.
A Doll's House premiered at the Royal Danish Theatre in Copenhagen, Denmark, on the 21st of December 1879. Betty Hennings played Nora, Emil Poulsen played Torvald, and Peter Jerndorff played Dr. Rank. Every performance of the premiere run sold out.
Nora was based on Laura Kieler, a close friend of Ibsen who, like the character, secretly took out an illegal loan to fund her husband's tuberculosis treatment. When the debt was discovered, her husband divorced her and had her committed to an asylum. She later returned to her family and went on to become a well-known Danish author, living to the age of 83.
Copyright laws of the time could not protect Ibsen's original ending in Germany, and the actress Hedwig Raabe refused to perform the play as written. To prevent a lesser dramatist from rewriting it without his input, Ibsen created an alternate ending in which Nora collapses at the sight of her sleeping children and appears to stay. He later called this ending a "barbaric outrage" on his own play.
The first edition, published in Copenhagen on the 4th of December 1879, printed 8,000 copies and sold out within a month. A second edition of 3,000 copies followed on the 4th of January 1880, and a third edition of 2,500 was issued on the 8th of March.
Ibsen denied it. In a speech to the Norwegian Association for Women's Rights in 1898, he said he had written the play without any conscious thought of making propaganda, describing his goal as "the description of humanity." Despite his denial, the play is widely associated with feminism and was included in Miriam Schneir's anthology Feminism: The Essential Historical Writings.
A Doll's House by Henrik Ibsen held the distinction of being the world's most-performed play in 2006, the centennial year of Ibsen's death. UNESCO also inscribed Ibsen's autographed manuscripts of the play on the Memory of the World Register in 2001.