Philip Marquam was the 8th child of Philip Winchester Marquam (b England) and Charlotte Poole (b Maryland, the daughter of Henry Poole, a wealthy planter, whose plantation stands at Poolville, MD). As a lawyer, his career spanned Oregon and California. Multnomah County Judge (1862 - 1870), state legislator (1882). As a real estate developer, he was for many years the largest landowner in Multnomah County. Builder of the Marquam Grand Opera House, later named the Orpheum Theater.

Philip Marquam's obituary, compliments of the Friends of Riverview:

The Oregonian (Portland, OR)
May 8, 1912
P. A. MARQUAM DIES ON WEDDING DATE
Pioneer Jurist of Portland Passes on 59th Anniversary of Marriage.
END COMES AT 12:17 A. M.
Surviving Members of Immediate Family at Bedside; Veteran Battles With Death Through Long Period of Unconsciousness
On the 59th anniversary of his wedding, Judge Philip A. Marquam, aged 89, pioneer of West and one of the original founders of Portland, succumbed to the slow ravages of cerebral hemorrhage this morning at 12:17 o'clock at the home of his daughter 648 Patton Rd.
The end came without the least resistance, as the veteran builder, philanthropist and jurist failed to regain consciousness since the apoplectic stroke Saturday morning. The tenacity with which he clung to life, despite his low vitality, was characteristic of the strength of the jurist throughout his life.

The immediate surviving members of the family were at the bedside when the end came. For several days his pulse has been too low to be detected. Those at the bedside were: T. A. Marquam, a son of Fairbanks, Alaska; Mrs. A. T. Velton, a daughter of Seattle; Mrs. C. C. Prince, Mrs. Jessie McLaughlin, Mrs. Charles Hill, all daughters; Gus and Will Marquam, sons, and Dr. Charles E. Hill son-in-law and attending physician.
End Comes on Anniversary
While the end has been expected hourly for several days, it was a peculiar incident that the aged jurist lived to the 59th anniversary of his wedding by just a few minutes. He was married May 8, 1853.
No funeral arrangements have been made. The body is in charge of the Edward Holman Undertaking Company.
Philip A. Marquam was born in Maryland in February 1823. He was of a family that had resided in the state from before the Revolutionary War. His maternal grandfather, Henry Poole, was one of the most extensive planters and prominent citizens of his day.
The father of Judge Marquam removed to Indiana in his son's boyhood, and the family lived on a farm in that state when it was a frontier. The limited resources of the family made it necessary for the boy to assist with the farm work. His desire for knowledge, however, was so great that often while following the plow he would reas such books as he could secure. In this way he acquired and education. He studied law with a Representative in Congress from Indiana. Afterwards e entered the Bloomington Law School, graduating in 1847. Judge Marquam practiced law for a short tim in Indiana.
California First Goal
Judge Marquam crossed the plains to California in 1849 and began the search for gold in the Sacramento district. Later he was chosen Judge of Yolo County, which position he held until his departure for Oregon in 1850.
Upon his arrival in Portland, Judge Marquam opened a law office. He was elected judge of Multnomah County in 1862. After his retirement from office he devoted his time to the real estate business.
The 61 years that Mr. Marquam passed as a resident of Portland are interwoven with the history of the city itself. The story of his early struggles is the history of the upbuilding of Portland and the sincerity and kindness of the man, his ruggedness and determination stand out at every period of his career.
Mr. Marquam came to Portland, August 13, 1851 and May 8, 1853, married Miss Emma Kern. Four sons and seven daughters were born to them. Those who survive are Mrs. Penumbra Kelly, Gus Marguam, William Marquam, Mrs. C. C. Prince, Mrs.Jessie McLaughlin, Mrs. Charles E. Hill, Mrs. C. C. Newcastle, Mrs. A. K. Veltin and T. A. Marquam of Fairbanks, Alaska.
Immediately after marriage he took up residence in a new home that he had built for himself in the block on which the Marquam and other buildings now stand. The house was on the corner where now stands the Maegley-Tichnor building, and only three years ago was torn down to make way for a more modern structure. Mr. Marquam bought the bock in early days for $500.
Peculiar Architecture In Home
Because of its peculiar architecture, the residence was known as "The Little New England Cottage." Here Mr. Marquam dispensed his generosity to those in need. He is particularly known for his kindness to immigrants.
The Marquam Theater was one of his early achievements and at the time it was built was the most modern playhouse on the Pacific Coast. The Marquam building of eighty stories, modern and fireproof, was another monument to the pioneer. The building with the theater cost him $600,000.
The theater was completed in 1890, two years before the completion of the building proper. The only other theater in the city then was known as the Tivoli Theater , which is the Empress Theater of today. When the Marquam building was being built, brick makers in Portland raised the price of brick. Mr. Marquam's fighting spirit was aroused at this and he established his own brickyard.
Mr. Marquam was active in securing the construction of the Morrison-street-bridge, and also in securing a reduction in the fates on the Stark-street ferry from 25 cents to 10 cents, while he was County Judge.
The building of the Morrison-street bridge resulted in a protracted legal fight that was carried into the Untied States Supreme Court and lasted more than 10 years. Mr. Marquam and his associates were victorious but the funds of the promoting company had been depleted. Mr. Marquam unwilling to abandon the project, after he had made a successful fight for it induced the Pacific Bridge Company to build it.
Fight For Railroad Led
In 1883, when a railroad from the East was building westward, Mr. Marquam led the fight to induce it to make its terminus at Portland. He was successful and the road, now the O. W. R. & N., gave Portland its first rail connection with the country at large. With Governor Grover and Colonel W. W. Chapman, a wealthy land owner, he went East and negotiated with the railroad people. He gave 160 acres along the Base Line road nine miles east of Portland to the company and assisted in raising a bonus.
In 1884 he aided in persuading Henry Villard to build the Portland Hotel and took stock in the company. He bought the old Central School building, which stood on the present Portland Hotel site, and moved it to where the Selling building now stands. He equipped it and gave it to the school district for school purposes. Two years ago the school building was demolished.
During his incumbency as County Judge, which extended through two four-year terms, Mr. Marquam built the old Courthouse, which was torn down last Fall, and he also bought the property where the old county pore farm was established, along Canyon road.
Mr. Marquam owned the first race course in Portland, known as the East Portland Race Course. The track was situated in what now is known as Rossmere.
In early days Mr. Marquam owned Fulton and Fulton Park, comprising 100 acres, 60 acres where Riverview Cemetery is situated, and Marquam Hill, comprising 98 acres. He lost the Marquam Hill property, which has been renamed Healy Heights and Virginia Heights. He sold his Fulton property for $225,000. and his River view property for $150,000. He also owned small tracts in different parts of Portland. He resided for many years on Marquam Hill, but when his wife died 10 years ago he moved to the home of Mrs. C. C. Prince.