What does the "JS" refer to ?

W.H. Auden's poem, The Unknown Citizen, begins with an interesting epigraph:

To JS/07 M 378
This Marble Monument
Is Erected by the State)

The meaning of the alphanumeric inscription on the marble monument of the unknown citizen has been a matter of great discussion. Some argue that the inscription mirrors our social security number scheme and that it contains identifying personal information. Others argue that the alphanumeric inscription means nothing more than a symbol of the power of a totalitarian state. Either way, the JS/07 M 378 inscription is interesting.

'JS' itself may stand for the initials of the unknown citizen's first and last name. The numbers '07' and '378' may well have been randomly allocated, while the letter 'M' may classify the unknown citizen as male. Yet, this is all a matter of conjecture. If you look at how the United States social security numbers were historically assigned, the first three numbers held geographical significance and were known as Area Numbers. The middle two were known as the Group Numbers, and the last four digits were the Serial Numbers. However, since 2011, the Social Security Administration has changed to a randomized system. You can read about it below:

The SSN Numbering Scheme.

The new SSN Randomization Scheme.

Myths about the SSN Numbering Scheme.

Yet, the numbers on the social security cards (past and present) never held identifying information about someone's date of birth, age, or even race. Likewise, the numbers used by the Nazis or other totalitarian regimes throughout history never did so either. Rather, the practice of using numbers and letters in place of names was a means of dehumanizing and marginalizing the populace the regimes were persecuting. So, when you look at JS/07 M 378, you are looking at Auden's commentary about totalitarian regimes; interestingly, he wrote this poem in 1939, at a time when the Nazis were preparing to unleash a full scale implementation of their ethnic cleansing program on an unsuspecting Jewish populace.

Auden's poem is also a satire criticizing the loss of individuality in a world focused on standardization and efficiency. Today's world, so focused on technology and mechanization, further erodes the identity of the individual. The unknown citizen in Auden's poem is praised because he never made waves when he was alive; in other words, he conformed in all things to the government-sanctioned image of a model citizen. We don't know his name, his personal goals, or anything specific about him; we only know him by letters and numbers. Likewise, our social security numbers contain no pertinent information about us; however, our ability to apply for certain work and travel documents and to collect social security benefits hinges on possession of these numbers. In other words, we have to conform to a standardized system in order to function in our world, the kind of system Auden criticized.