Question: Mission San Rafael Arcángel was founded in 1817 as a medical "asistencia" ("sub-mission") of Mission San Francisco de Asís, it was a hospital to treat sick Native Americans, making it which regions, first sanitarium that was founded in 1769 by Gaspar de Portolà, was a polity of New Spain?

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Pedro Font: Pedro Font (1737-1781) was a Franciscan missionary and diarist.  He was born in 1737 in Girona, Catalonia, Spain.  Font received his training at Querétaro Missionary College.  From 1773 to 1775, he served at Mission San José de Tumacácori in Pima Country.  He was the chaplain of Juan Bautista de Anza's expedition that explored Alta California from 1775 to 1776.  Font authored the diary "With Anza to California", the principal account of the expedition.  While a member of the expedition, Font created one of the first maps of San Francisco Bay in early 1776.  He also identified the site for the proposed Mission San Francisco de Asís, which would be established later that year by Fathers Junípero Serra and Francisco Palóu.  Font was also involved in the excommunication of then-military governor Fernando Rivera y Moncada, whose use of force on a neophyte is described in detail in "With Anza to California".  Font later served at Mission Santa Teresa de Atil, Mission Santa Maria Magdalena, Mission San Pedro y San Pablo del Tubutama and La Purísima Concepción de Caborca prior to his death at the "visita" of San Diego del Pitiquito in 1781.

Alta California: Alta California (English: Upper California ), founded in 1769 by Gaspar de Portolà, was a polity of New Spain, and, after the Mexican War of Independence in 1822, a territory of Mexico.  The region included all of the modern American states of California, Nevada, and Utah, and parts of Arizona, Wyoming, Colorado and New Mexico.

USNS Mission San Francisco (T-AO-123): USNS "Mission San Francisco" (T-AO-123) was a "Mission Buenaventura"-class oiler that served in the United States Navy.  The ship was originally intended as USS "Contoocook" (AO-104) for the U.S. Navy but her acquisition was canceled.  The ship, a Type T2-SE-A3 tanker, was completed as SS "Mission San Francisco" and delivered after the end of World War II.  The tanker was acquired by the U.S. Navy in 1947 as USS "Mission San Francisco" (AO-123), but was transferred to the Military Sea Transport Service (MSTS) upon its creation in 1949.  During a second stint with the MSTS that began in 1954, "Mission San Francisco" collided with the freighter "Elna II" in the Delaware River coast and was declared unsalvageable by the U.S. Navy.  The ship was one of two U.S. Navy vessels named for the Franciscan mission of San Francisco de Asís located in San Francisco, California.

Vicente Pascual Oliva: Father Vicente Pascual Oliva, O.F.M. (born 18th century, died January 2, 1848) was Catholic a priest of the Franciscan Order, and a Spanish missionary in California during the 19th century.  He was born in Martin del Rio in the ancient kingdom of Aragon, and joined the Order in the convent of Nuestra Señora de Jesus, Zaragosa, on February 1, 1799.  He left for the Apostolic College of San Fernando de Mexico on March 29, 1810; form there he departed for Alta California in early July, 1811 but due to various setbacks and illness did not reach Monterrey until August 1813.  Fray Oliva was allowed to officiate over his first baptism at Mission San Carlos Borromeo de Carmelo on October 28 of that year.  Soon thereafter he was transferred to Mission San Fernando Rey de España, where he also assisted the fathers of Mission San Gabriel Arcángel until the fall of 1815.  Beginning his ministry at Mission San Francisco de Asís on November 18, 1815, he continued there until the fall of 1818, when he was transferred to Mission San Miguel Arcángel.  He served there for approximately two years before being called to Mission San Diego de Alcalá, where he resided until early 1832 until being sent to Mission San Luis Rey de Francia to manage the temporal affairs of that outpost.  Father Oliva made his first entry in the Baptismal Register of Mission San Juan Capistrano on September 6, 1846.

Chief Marin: Chief Marin (born about 1781, died March 15, 1839) was the "great chief of the tribe "Licatiut"" (a branch of Coast Miwok native to present-day Marin County, California), according to General Vallejo's semi-historical report to the first California State Legislature in 1850.  Historical records indicate that he was baptized as a young man at Mission San Francisco de Asís (of San Francisco, California) in 1801 and eventually moved to Mission San Rafael Arcángel (of San Rafael), where he was an "alcalde" in the 1820s.  Marin died on March 15, 1839 of natural causes.  Marin County and the Marin Islands are believed to be named in his honor.

Gaspar de Portolà: Gaspar de Portolà i Rovira (1716–1786) was a Spanish soldier and administrator in New Spain and became the founder and first governor of Alta California, as commander of the Spanish colonizing expedition on land and sea that established San Diego and Monterey.  Portolà also led the first land expedition from San Diego to San Francisco.  He named many geographic features on the way, many of which are still in use.

San Pedro y San Pablo Asistencia: The San Pedro y San Pablo Asistencia was established in 1786, as a "sub-mission" to Mission San Francisco de Asís in the San Pedro Valley at the Ohlone village of "Pruristac".  The site is located within the bounds of the Rancho San Pedro (home to the Sánchez Adobe) in what today is the town of Pacifica.

USNS Mission San Rafael (T-AO-130): SS "Mission San Rafael" was a Type T2-SE-A2 tanker built for the United States Maritime Commission during World War II.  After the war she was acquired by the United States Navy as USS "Mission San Rafael" (AO-130).  Later the tanker transferred to the Military Sea Transportation Service as USNS "Mission San Rafael" (T-AO-130).  She was a member of the "Mission Buenaventura"-class oiler and was named for Mission San Rafael Arcángel, she was the only U.S. Naval vessel to bear the name.

Mission Dolores mural: The Mission Dolores mural is an 18th-century work of art in the Mission San Francisco de Asís, the oldest surviving structure in San Francisco.  In 1791, the Ohlone people, Native Americans of the San Francisco Bay and laborers for the church, painted the mural on the focal wall of the sanctuary.  Five years later, an altarpiece known as a reredos, was constructed in front of the mural, blocking it from view for more than two centuries.  The mural remained mostly unseen in the intervening years, decaying slowly as it was protected from light and moisture behind the reredos enclosure.

Mission San Rafael Arcángel: Mission San Rafael Arcángel was founded in 1817 as a medical "asistencia" ("sub-mission") of Mission San Francisco de Asís.  It was a hospital to treat sick Native Americans, making it Alta California's first sanitarium.  The weather was much better than in San Francisco, which helped the ill get better.  It was not intended to be a stand-alone mission, but nevertheless grew and prospered and was granted full mission status on October 19, 1822.

Supporting paragraphs: Mission San Rafael Arcángel Alta California
Answer: Alta California