Twins of Narvik, Part I

The Twins of Narvik is a historical fiction of the period from 1912-1945 culminating in the events taking place in Norway in World War II. These include the Naval and land battles around the Arctic Port Town of Narvik, the attack on the Heavy Water facilities at Vemork, and the hunt for the German Battleship Tirpitz.
The novel begins as a mystery, with a Texan Billionaire seeking to understand why his mother, as she slipped into dementia before her death, claimed to have been born in Norway and to have given birth to a pair of otherwise unknown twin sons. She further claimed her twin sons fought for their country in World War II. Diane Sterling and her international agency are hired to investigate this claims.
The story she uncovers is one of multiple families over the time period of 1912 - 1945, spanning the countries of Norway, Poland, England, Scotland and the United States. As the story unfolds, the following events are incorporated into the storyline: The Gallipoli and the Dardanelles Campaigns from World War I and from World War II, the Invasion of Poland, the original breaking of the Enigma code, the creation of the Independent Polish Highland (Podhale) Rifle Regiment, the Dunkirk Evacuation, the Battle of Britain, the Death of General Sikorski at Gibraltar and the aforementioned events in Norway.
NOTE THIS IS PART ! OF A TWO PART TITLE (Many of the events listed above are in Part 2)