Short answers, pulled from the story.
Louis Bonaparte was a younger brother of Napoleon I, born on the 2nd of September 1778 in Ajaccio, Corsica. Napoleon appointed him King of Holland in 1806 when he replaced the Batavian Commonwealth with the Kingdom of Holland, intending Louis to serve as a compliant French prefect over the territory.
Louis abdicated on the 1st of July 1810 after refusing Napoleon's demands to reduce Dutch investors' loans by two-thirds and to supply troops for the Russian invasion. Napoleon withdrew most French forces from Holland, leaving Louis unable to repel a British landing of 40,000 troops in 1809, and then used that military failure as grounds to demand his brother's removal.
Louis earned the title Louis the Good for personally overseeing relief efforts after two major disasters in Holland: a gunpowder ship explosion in Leiden in 1807 and a major flood in 1809. Napoleon reportedly disapproved, remarking that when a king is called good it means he has failed in his rule.
After fleeing Haarlem in July 1810, Louis took the title Count of Saint-Leu and accepted asylum from the Austrian Emperor Francis I. He lived in Graz between 1811 and 1813, turned to writing and poetry, and was finally permitted to visit the Netherlands in 1840 under King William II. He died from a stroke on the 25th of July 1846 in Livorno.
Napoleon III was Louis Bonaparte's youngest son, born Charles Louis-Napoleon Bonaparte in 1808. He established the Second French Empire in 1852 and ruled as Emperor until 1870.
Louis married Hortense de Beauharnais on the 4th of January 1802 in a match arranged by Napoleon. Hortense was the daughter of Empress Josephine and thus Napoleon's stepdaughter. The marriage was largely loveless; Hortense resisted living in Holland, refused Louis's demand that she renounce her French citizenship, and deliberately avoided him throughout his reign.