What is a Fugue? A Complete Guide

A fugue is a type of compositional technique that makes use of imitative counterpoint. In these often highly intricate works, an initial theme is taken and then imitated and expanded upon throughout the fugue. Fugal writing might make up just a part of a piece, or the whole composition might be a fugue. Whilst fugues are most commonly associated with the music of the Baroque period, and particularly with composer Johann Sebastian Bach, there are examples of the genre from a range of eras, as well as some that are from outside of the Western classical tradition.

In this article we’ll investigate the structure of a fugue and take a look at some famous examples of fugues and their composers.

What is the Difference Between a Fugue and a Canon?

The word counterpoint refers to the relationship between two or more musical lines which are played at the same time and have a shared harmonic reference point, but which are independent in their rhythm and melodic shape.

Fugues and canons both use imitative counterpoint, and both forms were particularly popular during the Baroque period, but there are some key differences between them.

In a canon the initial theme is generally still being stated when another voice, the follower, starts to imitate it, so they overlap.

However, in a fugue the theme (or the subject, as it is called in a fugue) is usually fully stated before it is imitated in another voice.

As we’ll see, fugues also tend to follow a relatively complex structure, whereas canons can vary hugely in complexity, from simple rounds such as “Row, Row, Row Your Boat”, to complicated works like Igor Stravinksy’s Double Canon.

However, there tend to be sections of a fugue that allow for more imitative freedom, in comparison to the more strict imitation that is typically found in canons. 

Technical Terms

Voices

Fugues contain independent lines or parts, which we call voices.

These might be sung or played by various instruments, or they might just be clearly distinct linear voices within a keyboard work.

Fugues are written for two or more voices: more than one voice is required to achieve counterpoint and for one voice to imitate the other.

Most of the fugues in Bach’s famous book The Well-Tempered Clavier are written for three or for voices, but some are for two or five voices.

Subject

The subject is the fugue’s main theme: a short, single-line melody in the tonic key of the piece.

It is heard in full before we hear any imitation.

It often lasts for just a few bars.

Answer

After the subject has been stated we hear it again, but this time it is transposed to a new key – usually the dominant, or occasionally the subdominant.

If it has been transposed exactly, with exactly the same intervals between each note as the initial subject, it is referred to as a real answer.

Sometimes, however, it may need to be altered slightly in order to fit the underlying harmony.

In this case it is called a tonal answer.

Countersubject

Whilst the second voice plays the answer, the first voice starts with some new melodic material, which now accompanies the second voice.

If this material is to be reused later, it is called the countersubject; otherwise, this is just referred to as free counterpoint.

Structure of a Fugue

A fugue tends to be divided up into clear sections:

Exposition

This is the opening section where all of the voices are introduced and we hear the subject and answer.

In a four-voice fugue, we would typically hear the first voice play the subject, the second voice play the answer, the third voice play the subject again, and the fourth voice play the answer again.

The exposition is over once every voice has been introduced and stated its subject or answer.

‘Fugue Exposition 10’ by Gedalge

Episode

An episode is a section in which we do not hear the fugue’s subject, although it may use some material from the exposition.

It might just be a single bar or a relatively long chunk of music.

It often has the purpose of preparing for another treatment of the subject in a new key.

Development

The middle section of a fugue will normally see entries of the subject in a selection of new keys, with these separated by episodes.

Various compositional devices can be applied to the subject to add interest for the listener.

The subject might be mutated somehow.

For example, a minor subject could be made into a major one, or vice versa, or we could make the note values of the subject longer (this is called augmentation) or shorter (this is called diminution).

Or we could hear the subject played over a pedal point (a sustained note in the bass line) to create a temporary sense of tension.

A common technique is called stretto, which is where we hear a second voice begin its subject or answer before the previous voice has finished its statement, so we hear both at the same time.

A false entry is where the start of the subject is played before the phrase morphs into something else.

The development section is where the composer gets to showcase their virtuosity and make things as complex as they like.

Final section

This is where we return to the subject and answer in the tonic key.

There may also be a coda.

Early History of the Fugue

The term fugue or fuga was initially used to describe canons, which first developed in the 13th Century.

However, the art of the fugue as we now know it really developed in the 17th Century with composers like Jan Pieterszoon Sweelinck and Girolamo Frescobaldi.

Slightly later, George Frideric Handel used fugal writing in his oratorios.

J.S. Bach was an absolute master of fugal writing.

His books The Well-Tempered Clavier and The Art of the Fugue are considered bibles of the form, and, famously, he was able to improvise incredibly complex fugues at the keyboard.

He further demonstrated his skill by using complex techniques such double fugues, which utilise two subjects and two answers, which may later be combined.

J.S. Bach – ‘Prelude and Fugue in E-flat Major’

Fugues in the Classical and Romantic Periods

After the Baroque period ended fugues were no longer seen so frequently.

Composers would, however, make occasional use of fugal writing, often as a section within a larger work.

Wolfgang Amadeus Mozart studied counterpoint extensively and wrote fugal sections in a number of his religious choral works.

The final movements of a number of Joseph Haydn’s string quartets are written as fugues:

Joseph Haydn’s String Quartet – ‘Fuga a due sogetti’

Ludwig van Beethoven studied Bach’s Well-Tempered Clavier as a young musician, and often wrote fugal sections in his works, including passages of his famous Ninth Symphony.

His Grosse Fuge (meaning “Grand Fugue”) was written late in his career when he was completely deaf and was considered shockingly modern when it was first performed.

Grosse Fuge‘ by Beethoven

Felix Mendelssohn (who was deeply influenced by Bach), Johannes Brahms, Franz Liszt and Anton Bruckner all used fugues within their compositions during the Romantic period.

Fugues Since the 20th Century

Fugal writing arguably became more widespread during the 20th Century, along with a greater appreciation of music and techniques from the Baroque era in general.

Maurice Ravel’s Le Tombeau de Couperin, Béla Bartók’s Music for Strings, Percussion and Celesta, and Igor Stravinsky’s Symphony of Psalms are all important 20th Century works which make use of fugal writing, whilst of course sounding nothing like J.S. Bach, despite being influenced by his techniques and concepts.

Leonard Bernstein’s Prelude, Fugue and Riffs marries Baroque forms with jazz-influenced modern classical composition, with the middle part written as a complex fugue for the saxophone section.

Here it is presented and conducted by Bernstein himself:

Leonard Bernstein – ‘Prelude, Fugue and Riffs’

There are also examples of fugues from outside of classical music.

John Lewis’ “Concorde”, written for his band the Modern Jazz Quartet, is one such example.

Meanwhile, “On Reflection” by the band Gentle Giant takes the influence of Bach’s contrapuntal writing and places it in the context of 1970s progressive rock:

‘On Reflection’ by Gentle Giant

Summary

So, that brings us to the end of our look at fugues.

We hope that it’s given you a better understanding of the fugue as a compositional technique, and that you’ve enjoyed listening to some incredible examples of fugues from across the history of Western classical music.

As well as looking at pieces by the likes of Bach, Beethoven, Bernstein, and even the rock band Gentle Giant, we’ve also learnt about the inner workings and technical terms used in these wonderfully clever compositions.

Thanks for reading!