Sir Walter Scott, 1771-1832, was at the height of his popularity in the first half of the 19th century, and a number of his novels were turned into operas; Lucia, based on The Bride of Lammermoor, published in 1800, is the most popular of the Scott operas, although others, including Anna Bolena and Lucrezia Borgia are occasionally heard. (Arthur Sullivan's opera Ivanhoe, with which he intended to show the world that he was also a composer of serious works, has died a merciful death.)
The original libretto for Lucia was written by one Salvadore Cannerano, and he made changes in Scott's story which leave little more than the basic outline intact. According to Scott, an old Scottish family, the Ravenswoods, who lived in the Southeast lowlands near Midlothian, had come upon hard times, and were forced to vacate their castle and move to an old, semiruined tower known as the Wolfscrag. (Act III, Scene i, is set in the tower, but it is cut in this production, per usual.) Then to make matters worse,in the revolution of 1689 Lord Ravenswood sided with the Episcopal Tories who wanted to keep James II, a Roman Catholic, on the English throne. When James was deposed in favor of William of Orange and his wife Mary, Ravenswood was forced to sell his estate (except for Wolfscrag) to the Presbyterian Whig, William Ashton. Shortly thereafter, Lord Ravenswood died, and his twenty-year old son, Edgar, became the last of the line and the Edgardo of the opera.
William Ashton had three children; the youngest, seventeen-year old Lucy and the middle, Henry, became Lucia and Enrico respectively. In the opera, the oldest son does not appear; further, Lord William and his wife, Lady Ashton, are already dead before the action begins, although in the novel they are alive throughout. (In fact, Lucia and Edgar(do) meet for the first time when she is attacked by a mad bull while visiting her mother's grave and he saves her; in the novel, the same mad bull appears, but attacks Lucy and her father.) The villainy of the elder Ashtons is transferred, in the opera, to the brother Henry-Enrico. In fact it was Lucy's mother in the novel who was responsible for intercepting Edgar's letters and thus convincing Lucy to marry Arthur Bucklaw.
In Act II of the opera, we learn why Enrico Ashton is so anxious for his sister to marry Arturo. King William, he tells Lucia, has died, and the hated Mary will ascend the throne; since Mary opposes the political party (unnamed) to which he belongs, only Lucia's marriage to Arturo can (in some undescribed fashion) save the family from ruin. All this is, of course, a complete historical mish-mash. Queen Mary II died in 1694, her husband William III in 1702, and they were never at political odds, as the opera libretto implies. In the novel, Lucy's father is worried about losing his estate, but for a different reason. It seems that Edgar(do) is planning to appeal to the House of Lords to return his holdings, and Sir William, being a Whig and a Presbyterian, is afraid that the predominantly Tory and Episcopal Lords will rule against him. In both the novel and the opera Edar(do) appears just as the marriage contract has been signed. The resulting sextet (near the end of Act II) is one of the musical high points of the opera, with beautiful melody and rich sonority. And in both novel and opera Lucy-Lucia stabs her husband on their wedding night (Act III, Scene i of the opera). The resulting mad scene is the most celebrated part of the score. Lucia hallucinates that she is marrying not Arturo but Edgardo, and describes the imagined ceremony in exquisite and tragic detail.
One difference between opera and novel is that in the latter Arthur survives the attack and, after Lucy's death, leaves Scotland never to return. In the opera, of course, Lucia kills Arturo. In the opera, Edgardo stabs himself to death, while in the novel he disappears into the waters surrounding the tower. In either case he is certainly dead. His final, heartrending aria, expresses the certainty that he and Lucia will be reunited in heaven. Strangely enough, although one usually thinks of minor keys as expressing sorrow, the aria is written in the key of D Major, telling the listener that the resurrection into heaven of the two lovers is not tragic, but rather a source of eternal joy.