Snollygoster

Entry in progress—B.P.
   
Wiktionary: snollygoster
Etymology
19th century American English. Possibly from snallygaster, a mythical beast that preys on poultry and children, possibly from Pennsylvania Dutch schnelle geeschter, from German schnell, quick + geist, spirit.
Noun
snollygoster (plural snollygosters)
1.(slang, obsolete) A shrewd person not guided by principles, especially a politician.
 
The Free Dictionary
snol·ly·gos·ter (snl-gstr)
n. Slang
One, especially a politician, who is guided by personal advantage rather than by consistent, respectable principles.
[Perhaps alteration of snallygaster, a mythical beast said to prey on poultry and children, perhaps from Pennsylvania Dutch schnelle geeschter : Middle High German snl, quick (from Old High German) + Middle High German geist, spirit (from Old High German).]
   
(Oxford English Dictionary)
snollygoster, n.
Etymology:  Perhaps connected with snallygaster n., which is, however, of more recent appearance.
U.S. dial. and slang.
A shrewd, unprincipled person, esp. a politician. Also in other more or less fanciful uses (see quots.).
1846 Commonwealth (Frankfort, Kentucky) 7 Apr. 2/6   Now here I am a rale propelling, double revolving locomotive Snolly Goster, ready to attack anything.
1863 D. D. Emmett Black Brigade (song) 5   We am de snolly-gosters, An’ lubs Jim Ribber oysters.
1895 Columbus (Ohio) Dispatch 28 Oct. 4/3   A Georgia editor kindly explains that ‘a snollygoster is a fellow who wants office, regardless of party, platform or principles, and who, whenever he wins, gets there by the sheer force of monumental talknophical assumnacy’.
1912 Dial. Notes 3 590   Snolly-goster, a shyster.