Thema Mundi

[nablator]

From the Thema Mundi, to get to the 4-1-1-1 pattern takes only two simple changes, Mars is switched to its primary sign, which is Aries, and Saturn is changed to its alternate, which is Aquarius.

Pierre d'Ailly in his Vigintiloquium or De concordantia astronomie... (a treatise that consists in 20 arguments, several variants of the title in printed editions) composed in 1414, also gives Saturn's original position in Aquarius but Mars in Scorpio, Venus in Taurus, Mercury in Gemini.
   

Verbum decimumnonum.
[...]
Postremo ponemus planetas in eorum domibus (in quibus creati sunt) cum gradibus earum exaltationum.
Exceptis sole et luna qui in locis earum exaltationum ponendi sunt ut sequens tabula declarabit.
Saturnus ponitur in aquario in domo sua: alias in gradu suae exaltationis 21.
Jupiter ponitur in sagittario vel in piscibus secundum aliquos qui dicitur quod ibi magis gaudet in domo sua in gradu suae exaltationis 28.
Mars in scorpione in domo sua in gradu suae exaltationis 28.
Sol in ariete in gradu arietis suae exaltationis 19.
Venus in tauro in domo sua in gradu suae exaltationis 27.
Mercurius in domo sua in geminis in gradu suae exaltationis 15.
Luna in thauro in gradu suae exaltationis 3.

It seems that every astrologer had their own favorite arrangement.

From Laura Ackerman Smoller, History, Prophecy, and the Stars: The Christian Astrology of Pierre d’Ailly, 1350-1420 (1994, Princeton University Press) p. 65:

Having rejected what he calls the a posteriori method of figuring the world’s age by conjunctions, d’Ailly proceeds to an a priori determination. He acknowledges that he can offer only a conjecture, for his calculations require drawing up a horoscope with the location of all of the planets at the moment of their creation on the fourth day.25 D’Ailly was by no means the first to interest himself in the horoscope of Creation (or thema mundi). The subject comes up not infrequently in astrological literature — and in art — though with no great uniformity in solutions.26 It was an astrological common place that the degree of the ecliptic known as a planet’s exaltation corresponded to the position in which the planet was created. With such reasoning Julius Firmicus Maternus in the fourth century had sketched out a thema mundi, which was taken up in Macrobius’s widely read Commentary on the Dream of Scipio. Firmicus Maternus and those following in his footsteps assigned Aries to the prominent position of the mid heaven (medium celum) in the world’s horoscope and had the sun in the sign of Leo.27 Christian tradition, however, dictated that the world was created when the sun was at or near the vernal equinox (Aries 0°), so that the Creation, the Annunciation, and the Crucifixion might all fall (in theory) on the same date. Hence, the sun would have to be in Aries, and not in Leo as Firmicus Maternus would have it.

D’Ailly’s horoscope, accordingly, differs substantially from Firmicus Maternus’s. Drawing, as he claims, on Albumasar, he presents a horoscope that also has Aries in the midheaven, but with drastically different planetary positions. The planets, he says, are in their exaltations.28 The positions correspond more closely, though not exactly, to the exaltations given by Alchabitius than to those of Firmicus Maternus.

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I haven't found a source yet for Albumasar's and Alcabitius's versions of the thema mundi.