"An Imperial Marriage" by Arthur W. Marchmont is a novel written in the early 20th century. The story is set against the backdrop of the German imperial court, weaving a complex tapestry of romance, political intrigue, and personal sacrifice. The narrative primarily revolves around Althea Korper, whose life becomes entangled with the fates of Prince von Graven and other key figures as their relationships unfold amidst the machinations of high society. The opening of the story introduces us to Paul Bastable, a former Berlin correspondent, who becomes aware of a royal engagement between Prince von Graven and Princess von Altenvelt. Paul's emotions are immediately complicated by the revelation that the prince has fallen in love with Althea, his own love interest, leading to feelings of jealousy and concern. As tensions rise, Althea finds herself in a precarious situation when her identity is revealed to carry significant implications tied to her father, Baron von Ringheim, a figure linked to revolutionary politics. Allegiances shift as Althea seeks Paul's help to escape the threat of arrest, setting the stage for a thrilling exploration of romance and political strife in the face of impending danger. (This is an automatically generated summary.)