Alexander Campbell is the figure most associated with Kelloggism, the adoption of portions of Edward Kellogg's currency and banking theory by elements in the greenback and labor movements. In the course of my recent w0rk on Kellogg, I ran across Campbell's The True American System of Finance (1864) in the Samuel J. May Anti-Slavery Collection, a very nice digital archive at Cornell, which includes quite a number of works on currency and finance--a hot issue in the days of the first national currency in the US. (See, for example, "Greenbacks"; or, The evils and the remedy of using "Promise to pay to the bearer on demand" as a measure of value by Observer.) Campbell's work acknowledges its Civil War context, with the subtitle "the rights of labor and capital, and the common sense way of doing justice to the soldiers and their families : no banks, greenbacks the exclusive currency."
I had previously read Campbell's The true greenback : or the way to pay the national debt without taxes, and emancipate labor (1868), which appears as an appendix to the 1971 A. M. Kelley reprint of Kellogg's Labor and Other Capital, and both works are of much the same character. Kelloggism retained Kellogg's theory of the nature of money and his emphasis on the right of government to regulate interest rates, but maintained almost none of the practical features of his Safety Fund. This seems to be true of William Sylvis' adoption of Kellogg's ideas as well. (See his "What Is Money?") We know that Ezra H. Heywood flirted briefly with these ideas during his affiliation with the National Labor Union, but greenbackism was generally pretty far removed from the labor notes and mutual banks of the mutualist and individualist anarchist traditions.