Sadus came together as a quartet in 1984 of vocalist Darren Travis, guitarist Rob Moore, bassist Steve DiGiorgio and drummer Jon Allen, although it was to be two years until the first fruits of this liaison came into being with the 1986 D.T.P. (Death To Posers) demotape. These sessions led directly to the inclusion of two tracks on the 1987 Raging Death compilation album. Quick to capitalize on this achievement Sadus stuck their hands in their pockets to self finance the debut album pulling in Metal Church guitarist John Marshall as producer. The pace of progress was quickened as a deal with label Roadrunner Records was secured resulting in a further album Swallowed in Black and touring with the likes of Sepultura and Obituary.
Sadus was put on ice for 1991 as DiGiorgio opted to assist Death for their Human. With this added exposure Roadrunner re-released the Illusions debut retitled Chemical Exposure as SADUS regrouped for a summer American tour opening for Morbid Angel. Although a further album for Roadrunner, 1992's A Vision of Misery, resulted in a European headline tour, Sadus found itself labelless upon their return. Further setbacks occurred when DiGiorgio was inticed back to Death for the Individual Thought Patterns album and a subsequent year long bout of touring. DiGiorgio was to return for club shows with SADUS but before any momentum could be gained Moore bailed out.
Sadus continued as a trio crafting the Scott Burns produced Elements of Anger in 1997. The in demand DiGiorgio, along with drummer Jon Allen, also operated a side project Dragonheart (later Dragonlord) with ex-Vicious Rumours and present day Testament guitarist Steve Smyth and his fellow Testament six-stringer Eric Peterson. DiGiorgio teamed up with Iced Earth in late 2000.
News during the summer of 2002 would reveal that frontman Darren Travis and bassist Steve DiGiorgio was embarking on another all star union billed as Suicide Shift. The project allied the Sadus pairing with Testament vocalist Chuck Billy as well as drummer Per Moller Jensen of The Haunted and guest guitar from the much travelled, Death and Cancer guitarist James Murphy.
The Hammerheart label would put the band's original Death To Posers 1986 demo onto CD in 2003, adding a brace of cuts from a 1988 session, Certain Death, as a bonus.
Sadus announced they were to partner up with fellow thrash veterans Nasty Savage and high profile Finnish act Finntroll for European mainland dates in December. However, just days after the official press release confirming these shows the band withdrew as drummer Jon Allen's commitments to his 11 year old daughter, who had just undergone open heart surgery, took precedence.
Despite Steve DiGiorgio commitments in 2004 to Testament, the band did increase activity that year. In April the group toured Europe, taking in shows in in Greece, Italy, Sweden and appearing at Norway's Inferno Metal Festival in Oslo. DiGiorgio then took time out to record with Artension then hit the European festival circuit with Testament. Gigs in August marked a first for Sadus as they toured Chile alongside Torturer whilst on South American dates. New Sadus material would be laid down throughout September and October before DiGiorgio joined the ranks of Sebastian Bach's band for further European touring in December. The bassist would also be announced as a contributor to tecordings for Norwegian act Scariot in early 2005.
Sadus, together with producer Brage Finstad, entered Trident Studios in Pacheco, California to record their fifth album for a late summer release via Mascot Records. In March 2006 Jon Allen manned the drum kit for live work with Testament. That same month found DiGiorgio involving himself in a studio collaboration with singer Björn Strid, of Soilwork, Terror 2000 and Coldseed, Glen Alvelais from Forbidden, Testament and LD/50 and Jeremy Colson of the Steve Vai band, Marty Friedman, Michael Schenker, Apartament 26, Dali'S Dilemna and LD/50 repute.
On November 18 the band appeared at the Monterrey Metal Fest event at the at the Coca-Cola Auditorium in Mexico alongside Blind Guardian, Cathedral, U.D.O., Edguy, Obituary, Deicide, Leaves' Eyes, Bludgeon, Vainglory, Hydrogyn and Joe Stump's Reign of Terror.
Sadus was announced as teaming up with Destruction, Hirax and Municipal Waste for a North American tour throughout January and February 2007. However, the group dropped off these dates as new year broke. Sadus lined up the South American 'Fuera Por Sangre' dates hitting Venezuela, Ecuador and Colombia in April prior to supporting Obituary in Mexico during May. In 2009 Sadus veterans Jon Allen and Steve DiGiorgio were noted as founder members of Futures End.