How to view datetime stamp for history command in Zsh shell

I believe the HISTTIMEFORMAT is for Bash shells. If you're using zsh then you could use these switches to the history command:

Examples

$ history -E
    1   2.12.2013 14:19  history -E

$ history -i
    1  2013-12-02 14:19  history -E

$ history -D
    1  0:00  history -E
    2  0:00  history -i

If you do a man zshoptions or man zshbuiltins you can find out more information about these switches as well as other info related to history.

excerpt from zshbuiltins man page

Also when listing,
  -d     prints timestamps for each command
  -f     prints full time-date stamps in the US `MM/DD/YY hh:mm' format
  -E     prints full time-date stamps in the European `dd.mm.yyyy hh:mm' format
  -i     prints full time-date stamps in ISO8601 `yyyy-mm-dd hh:mm' format
  -t fmt prints time and date stamps in the given format; fmt is formatted 
         with the strftime function with the  zsh extensions described for 
         the %D{string} prompt format in the section EXPANSION OF PROMPT 
         SEQUENCES in zshmisc(1).  The resulting formatted string must be no 
         more than 256 characters or will not be printed.
  -D     prints elapsed times; may be combined with one of the options above.

Debugging invocation

You can use the following 2 methods to debug zsh when you invoke it.

Method #1

$ zsh -xv

Method #2

$ zsh
$ setopt XTRACE VERBOSE

In either case you should see something like this when it starts up:

$ zsh -xv
#
# /etc/zshenv is sourced on all invocations of the
# shell, unless the -f option is set.  It should
# contain commands to set the command search path,
# plus other important environment variables.
# .zshenv should not contain commands that produce
# output or assume the shell is attached to a tty.
#

#
# /etc/zshrc is sourced in interactive shells.  It
# should contain commands to set up aliases, functions,
# options, key bindings, etc.
#

## shell functions
...
...
unset -f pathmunge _src_etc_profile_d
+/etc/zshrc:49> unset -f pathmunge _src_etc_profile_d

# Created by newuser for 4.3.10

history -E or history -i or whatever DO NOT work for me.

zsh --version shows that zsh 4.3.6 (x86_64-suse-linux-gnu).

Then fc -li 100 works! It shows the recent 100 commands with timestamp :)

If you are using oh-my-zsh addon in zsh, history -E or history -i wont work (because it's aliased to fc -l 1).

As @juanpastas pointed out, try

\history -E

or

\history -i

or

fc -li 100