Best know as an American pulp author for Weird Tales, for which he wrote a series of stories about occult detective Jules de Grandin. He was the author of non-fiction legal and medical texts and editor of Casket & Sunnyside, a trade journal for mortuary jurisprudence. He also published fiction for Embalming Magazine, another mortuary periodical.
Disclaimer - please note that I wrote the introduction to the third volume in this series.
All 93 of these tales (including a serialized novel) were originally published by WEIRD TALES, where they rivalled in popularity the authors with whom we are more familiar today, such as Lovecraft, Robert E. Howard, and Clark Ashton Smith. They are basically adventure stories, usually with a supernatural or macabre theme, and many of them are quite fun, though they do tend to become a bit repetitious toward the middle of the cycle, and some of them (particularly the novel THE DEVIL'S BRIDE) may have interesting episodes without even coming close to succeeding as wholes.
I was only familiar with a few of these and their bad reputation among Lovecraft/Howard/Smith scholars prior to being asked to assist with this project, but ended up liking several of them for their social commentary, unusual treatment of familiar themes, lively plots, effective atmosphere, and striking "set pieces":
2 The Tenants of Broussac (Dec ‘25) 3 The Isle of Missing Ships (Feb ‘26) 9 The Grinning Mummy (Nov ‘26) 22 Restless Souls (Oct ‘28) 25 The Devil-People (Feb ‘29) 26 The Devil's Rosary (Apr ‘29) 41 Stealthy Death (Nov ‘30) 45 Satan's Stepson (Sept ‘31) 46 The Devil’s Bride (Feb - Jly ‘32) - the narrative told by the murdered woman's brother concerning their past 59 The Jest of Warburg Tantavul (Sept ‘34) 66 Satan's Palimpsest (Sept ‘37) 71 Incense of Abomination (Mar ‘38) 75 The Poltergeist of Swan Upping (Feb ‘39) 84 The Man in Crescent Terrace (Mar ‘46) 87 Lotte (Sept ‘46) 91 Conscience Maketh Cowards (Nov ‘49)
--Full Contents of the Three Volume Set--
VOLUME 1: *"By Way of Explanation" by Seabury Quinn * "My Life with Jules de Grandin" by Robert Weinberg * Robert Weiberg's five Prefaces to the Popular Libray paperback selections from the de Grandin corpus *"By Way of Explanation" by Seabury Quinn 1 Terror on the Links (Oct ‘25) [aka Horror on the Links] 2 The Tenants of Broussac (Dec ‘25) 3 The Isle of Missing Ships (Feb ‘26) 4 The Vengeance of India (Apr ‘26) 5 The Dead Hand (May ‘26) 6 The House of Horror (Jly ‘26) 7 Ancient Fires (Sept ‘26) 8 The Great God Pan (Oct ‘26) 9 The Grinning Mummy (Nov ‘26) 10 The Man Who Cast No Shadow (Feb ‘27) 11 The Blood Flower (Mar ‘27) 12 The Veiled Prophetess (May ‘27) 13 The Curse of Everand Maundy (Jly ‘27) 14 Creeping Shadows (Aug ‘29) 15 The White Lady of the Orphanage (Sept ‘27) 16 The Poltergeist (Oct ‘27) 17 The Gods of East and West (Jan ‘28) 18 Mephistopheles and Company Ltd (Feb ‘28) 19 The Jewel of the Seven Stones (Apr ‘28) 20 The Serpent Woman (June ‘28) 21 Body and Soul (Sept ‘28) 22 Restless Souls (Oct ‘28) 23 The Chapel of Mystic Horror (Dec ‘28) 24 The Black Master (Jan ‘29) 25 The Devil-People (Feb ‘29) 26 The Devil's Rosary (Apr ‘29) 27 The House of the Golden Masks (June ‘29) 28 The Corpse-Master (Jly ‘29) 29 Trespassing Souls (Sept ‘29) 30 The Silver Countess (Oct ‘29) 31 The House Without a Mirror (Nov ‘29) 32 Children of Ubasti (Dec ‘29) 33 The Curse of the House of Phipps (Jan ‘30) [aka The Doom of the House of Phipps] 34 The Drums of Damballah (Mar ‘30) 35 The Dust of Egypt (Apr ‘30)
VOLUME 2: *"By Way of Explanation" by Seabury Quinn *"My Father and I" by Seabury Quinn, Jr. 36 The Brain-Thief (May ‘30) 37 The Priestess of the Ivory Feet (June ‘30) 38 The Bride of Dewer (Jly ‘30) 39 Daughter of the Moonlight (Aug ‘30) 40 The Druid's Shadow (Oct ‘30) 41 Stealthy Death (Nov ‘30) 42 The Wolf of St Bonnot (Dec ‘30) 43 The Lost Lady (Jan ‘31) 44 The Ghost-Helper (Feb ‘31) 45 Satan's Stepson (Sept ‘31) 46 The Devil’s Bride (Feb - Jly ‘32) 47 The Dark Angel (Aug ‘32) 48 The Heart of Siva (Oct ‘32) 49 The Bleeding Mummy (Nov ‘32) 50 The Door to Yesterday (Dec ‘32) 51 A Gamble in Souls (Jan ‘33) 52 The Thing in the Fog (Mar ‘33) 53 The Hand of Glory (Jly ‘33) 54 The Chosen of Vishnu (Aug ‘33) 55 Malay Horror (Sept ‘33) 56 The Mansion of Unholy Magic (Oct ‘33) 57 Red Gauntlets of Czerni (Dec ‘33) 58 The Red Knife of Hassan (Jan ‘34) 59 The Jest of Warburg Tantavul (Sept ‘34)
VOLUME 3: *"By Way of Explanation" by Seabury Quinn *"The Occult Delights of Jules de Grandin" by Jim Rockhill 60 The Hands of the Dead (Jan ‘35) 61 The Black Orchid (Aug ‘35) 62 The Dead-Alive Mummy (Oct ‘35) 63 A Rival From the Grave (Jan ‘36) 64 Witch-House (Nov ‘36) 65 The Children of the Bat (Jan ‘37) 66 Satan's Palimpsest (Sept ‘37) 67 Pledged to the Dead (Oct ‘37) 68 Living Buddhess (Nov ‘37) 69 Flames of Vengeance (Dec ‘37) 70 Frozen Beauty (Feb ‘38) 71 Incense of Abomination (Mar ‘38) 72 Suicide Chapel (June ‘38) 73 The Venomed Death of Vengeance (Aug ‘38) 74 Black Moon (Oct ‘38) 75 The Poltergeist of Swan Upping (Feb ‘39) 76 The House Where Time Stood Still (Mar ‘39) 77 Mansions in the Sky (June-Jly ‘39) 78 The House of the Three Corpses (Aug ‘39) 79 Stoneman’s Memorial (May ‘42) 80 Death's Bookkeeper (Jly ‘44) 81 The Green God's Ring (Jan ‘45) 82 Lords of the Ghostlands (Mar ‘45) 83 Kurban (Jan ‘46) 84 The Man in Crescent Terrace (Mar ‘46) 85 Three in Chains (May ‘46) 86 Catspaws (Jly ‘46) 87 Lotte (Sept ‘46) 88 Eyes in the Dark (Nov ‘46) 89 Clair de Lune (Nov ‘47) 90 Vampire Kith and Kin (May ‘49) 91 Conscience Maketh Cowards (Nov ‘49) 92 The Body Snatchers (Nov ‘50) 93 The Ring of Bastet (Sept ‘51)