Short answers, pulled from the story.
Frederick William I was King in Prussia and Elector of Brandenburg from 1713 until his death in 1740, and he was known as the Soldier King, or Soldatenkonig. He was born in Berlin on the 14th of August 1688 and was also Prince of Neuchatel.
Frederick William I earned the name Soldier King because he prioritized military expansion above all else. He expanded the Prussian Army from 38,000 men in 1713 to 80,000 by 1740, introduced the canton system, and equipped the infantry with the iron ramrod to raise its rate of fire.
Frederick William I dismissed his father's corrupt Cabinet of Three Counts in 1713 and rebuilt the ruined state finances by raising excise taxes and taxing the nobility's land. He dictated the Regulations for State Officials, a manual of 35 chapters and 297 paragraphs that set out the precise duties of every public servant in Prussia.
Frederick William I revoked the charter of the Brandenburg Africa Company in 1717 and sold the Brandenburg Gold Coast to the Dutch West India Company that same year. He was unwilling to spend money on the colony or the Prussian Navy, preferring to direct state revenues toward enlarging the army.
Frederick William I had a hostile relationship with his son Frederick, beating and humiliating him for preferring music, books, and French culture. After Frederick tried to flee to England, the king had his tutor Hans Hermann von Katte beheaded before the prince's eyes, though the two later reached civil terms before the king's death in 1740.
Frederick William I was finally laid to rest in 1991 on the altar steps of the Kaiser Friedrich Mausoleum in the Church of Peace on the palace grounds of Sanssouci. His coffin had moved several times, including hiding in a salt mine outside Bernterode during World War II, reburial at St. Elizabeth's Church in Marburg in 1946, and a stay at Hohenzollern Castle from 1953.