EL SALVADOR
All that warring has been going on in an area the size of
Massachussetts.  The rebel stronghold is about 25 miles from
the capital.  Imagine that.
Immediately prior to the European invasion the country
was subject to the Aztecs of Tenochtitlan.  The locals built
in stone, made fine pottery, and collected gold.  Four years
after Cortez slew Moctezuma in 1524, he sent Pedro de
Alvarado to take a look at the Pacific hinterland.  Alvarado
was beaten back by superior forces.  No quitter, he returned
the following year and seized the local capital, Cuscatlan.
The Spanish stayed, founded San Salvador and other towns,
divided up the land into estates, made the Indians into
slaves and bonded servants.  The region was attached to the
Captaincy-general of Guatemala throughout the colonial
period.
In 1821 the Spanish administration in Central America
collapsed.  Emperor Iturbide in Mexico annexed Guatemala
forthwith and made preparations to march south.  Faced with
the threat the Salvadoran Congress drafted an "Act of
Annexation" and declared itself a state within the USA.  Our
own Congress decided it would rather not get involved and
deep sixed the idea.
Iturbide had his southern campaign all wound up and ready
to go when he was overthrown.  His commander, General
Fiesola, turned around and became a champion of an
independent Central American Federation.  A constituent
assembly was gathered in 1823 and a consitiution
established.  Though coins were issued in the name of the
"Central American Republic" the entity never really got off
the ground.  States started seceding almost from the start,
with only Salvador remaining committed to union.
PROVISIONALS
Before the final dissolution of the Federation in 1838
Salvador issued the rare silver provisionals.  There are a
large and probably growing number of minor varieties, but
all are very hard to find.  One will often suspect a given
piece, but it is a bit hard to tell, there are so few
originals around.  These are the kind of coins that an
advanced but budget minded collector will attempt to acquire
in aG with a hole, but they're no less scarce in that kind
of grade and will still get a very high price (relatively
speaking of course).  I've never seen one go under $100.00.
COUNTERMARKS
The government started countermarking coins in 1831.  How
many types are there?  Five, plus the "SAP" mark found
rarely on CAR and Salvador provisionals, the attribution of
which no one has pinned down yet.  The volcano mark was used
in 1830 and 1839 and is rare.  The national arms types are
common on wiped ½ and 1 real cobs ("common" in this case
meaning a few show up in any given year), scarcer on British
coins and milled colonial minors, and rare on 4 and 8
reales.  "R" countermarks on mostly Guatemala minors are
findable, usually in low grade, often holed.  The same mark
on 4 and 8 reales is rare.  The "Type V" test mark is at
least very scarce.
PESOS
The first regular coins are the 1889 1¢ and 3¢.  The 1¢
can be found in uncirculated, but the 3¢ is tougher.  The
same types dated 1913 are scarcer and tough in Unc.  The
copper "Liberty cap" centavos of 1892-3 are perhaps a bit
easier to find than their high price would indicate.  I've
seen , oh, "several" in high grade (AU) over the years,
always offered at a decent discount.
Silver and gold coins began in 1892, with metal content
set to match Guatemalan (and French) coins.  Of the minors
the 5¢ is most easily found, 10¢ least.  The "flag" type 50¢
and peso are scarce, but the "Columbus" types of those
denominations are no problem.  The gold coins are all rare
and hardly ever turn up in affordable worn condition.
The minor coinage petered out by 1894 but the pesos
continuedwith a few gaps until 1914 with the "heavy" and
"light" portrait varieties.  All of them will turn up if you
look for them except the 1896, and that is tough indeed.
The 1909 bronze ¼ real is scarce.  Silver minors of 1911
and 1914 are not uncommon in grades up to XF or so, but
anything better is scarce.  Copper-nickel minors were struck
fitfully from 1915.  None are really scarce, save perhaps
the 1940 10¢, but they typically come worn.  As usual with
many supposedly common early 20th century coins of small
countries high grades tend to be quite elusive.
COLONS
The first of this new denomination (equal to the old
peso) were struck in 1925 to commemorate the foundation of
San Salvador.  The silver colon is a toughish coin, usually
found in XF, rarely in choice uncirculated, and hardly ever
in less than VF.  The gold piece is something of a power
coin.  The 1¢ was switched from copper-nickel to bronze
starting in 1942, and most of these bronze coins can be
fairly easily found in uncirculated.  Copper-nickel 5¢
continued into the '70s, the main difference between the
early types and the later ones being that pre-1940 coins
style the national name "Republica del Salvador" while the
later ones eliminate the elision.  The good sized
copper-nickel 10¢ and even nicer sized silver 25¢ are
popular coins of a not particularly popular country.  High
grade examples get a small premium.  The silver 25 and 50¢
of 1953 are also popular, with demand for Uncs slightly
exceeding supply.
Massive quantities of the 1974 2 and 3¢ and the 1976 1¢
were stocked by wholesalers along with more modest supplies
of 5¢ and a few 10¢ of various dates in the '50s and '60s.
I believe all dates after 1972 of all the minors have been
wholesaled to some extent.
1971 and 1977 silver commemoratives are less common than
their contemporary Costa Rican counterparts, e.g., but are
fairly easy to find.  The gold is less available.
EXONUMIA
There is a rich series of tokens dating from the mid-19th
through 20th centuries.  In general terms the series is
considered with Guatemala midway between the very common
Costa Rican tokens and the rare Nicaragua, Panama, and
Honduras.  Salvadoran tokens tend to be priced in the $3-10
range.