In genius studies, last universal genius is a rarefied epitaph assigned to a select few of the group of universal geniuses, of which there are about a dozen, referring to a person said to have been the last of the lineage of geniuses to have a universal grasp of knowledge.
The following quote by German polymath Johann Goethe (who in his college years, circa 1767-70, simultaneously attempted mastery of medicine, chemistry, law, and religion) gives indication of the genius dividedness (see also: two cultures) in knowledge: 
“In all our academies we attempt far too much. ... In earlier times lectures were delivered upon chemistry and botany as branches of medicine, and the medical student learned enough of them. Now, however, chemistry and botany are become sciences of themselves, incapable of comprehension by a hasty survey, and each demanding the study of a whole life, yet we expect the medical student to understand them. He who is prudent, accordingly declines all distracting claims upon his time, and limits himself to a single branch and becomes expert in one thing.”
Of this universal geniuses, only three: Leibniz (1646-1716), Goethe (1749-1832), and Helmholtz (1821-1894), the middle of these three in the most predominant manner, are frequently assigned the very rarefied epitaph of "last universal genius", as shown in bolded text format below, of which the mean IQ of this group is 207, which can be taken as the mean IQ for an archetype last universal genius. 
(a) “Remarkable for his encyclopedic knowledge and diverse accomplishments outside the fields of philosophy and mathematics, he was perhaps the last universal genius, spanning the whole of contemporary knowledge.”
Author. (2003). The Houghton Mifflin Dictionary of Biography (quote, pg. 913). Houghton Mifflin Harcourt. (b) “Remembered for his philosophy of ‘preestablished harmony’ on one hand and his bitter feud with Isaac Newton of the invention of calculus on the other, Leibniz was, according to one modern writer, the ‘last universal genius.’ His famous claim that this is the ‘best of all possible worlds’, was later ridiculed by Voltaire in Candide”
Cutler, Alan. (2004). The Seashell on the Mountaintop: How Nicolaus Steno Solved the Ancient Mystery and Created the Science of the Earth (quote, pg. #). Penguin. (c) Kreeft, Peter. (2009). Socrates Meets Kant (quote: “Leibniz was one of the greatest geniuses in the history of human thought, perhaps the last universal genius”, pg. 24). Ignantius Press.
(d) The Universal Genius: Gottfried Leibniz (quote: "known as the last universal genius") (2010) – The Philosopher’s Zone, ABC.net.
(a) “We often hear that Goethe was the last man in the world who was a universal genius. By this it is meant that he can be compared with a figure of the Renaissance such as Leonardo da Vinci. To me it never seems that Goethe fills happily the role of modern Leonardo. He is called the last universal genius, of course, because it is impossible to think of anyone …”
Spender, Stephen. (1950). “Article” (quote). The Listener (pg. 151). Vol. 44.(b) “Scholars agree that Goethe was the last universal genius: practically nothing within reach of the human mind escaped his attention.”
Wadepuhl, Walter. (1932). Goethe’s Interest in the New World (quote, pg.). Publisher.(c) Donat, Sebastian. (2004). Goethe: A Last Universal Genius. Munchen: Wallstein.
“The matter of multiplicity of contributors needs no great explanation, for we are all used to this in the modern handbooks. I believe it is a common saying that Helmholtz was the last universal genius, and we are fast arriving at the point where even a single subject becomes too vast for one man. At any rate, whether or not any of my learned colleagues could write an entire chemical engineering handbook, I could not—hence the present form.”Other
— Donald Liddell (1922) Handbook of Chemical Engineering, McGraw-Hill
One recent reference cites Henri Poincare as being the last universal genius as follows: 
“The earliest work in radar polarimetry is found in the early 1950s [Sinclair, 1950]. The theory was inspired by the work of Stokes [Stokes, 1852] and of the ‘last universal genius’ Poincare , both of whom laid the basis for a unified formalism for electromagnetic waves, regardless of their state of polarization.”
Chronologically, according to year of reaction end (death), Hungarian chemical engineer and mathematician John Neumann, with 3+ universal genius citations, puts him as official "last universal genius" (see: universal genius page), but citation of this, other than herein, is wanting.
In the social sciences, one to have been called the "last universal genius of social science" is Max Weber (1864-1920) (IQ=170), the vicarious student of Goethe, who notably began reading Goethe's elective affinities theory, at the age of 14, hidden behind his primary school books, while in class, which is a rather apt epitaph being he was first to apply Goethe's self-proclaimed greatest theory in the social sciences. 
1. Quoted in Johann Hermann Baas, Henry Ebenezer Handerson (trans.), Outlines of the History of Medicine and the Medical Profession (1889), 842-843.
2. Didier, Massonnet, and Souyris, Jean-Claude. (2008). Imaging with Synthetic Aperture Radar (pg. 229). CRC Press.
3. Author. (1962). “Max Weber: the Scholar as Hero” Columbia University Forum (quote: “Max Weber the 'last universal genius of social science' is today the least known of the great thinkers”, pg. 31). Columbia University Press.
4. Liddell. Donald M. (1922). Handbook of Chemical Engineering, Volume 1 (quote, pg. ix). McGraw-Hill Company.